Human genetics
Overview
 
Human genetics describes the study of inheritance as it occurs in human beings. Human genetics encompasses a variety of overlapping fields including: classical genetics
Classical genetics
Classical genetics consists of the technique and methodologies of genetics that predate the advent of molecular biology. A key discovery of classical genetics in eukaryotes was genetic linkage...

, cytogenetics
Cytogenetics
Cytogenetics is a branch of genetics that is concerned with the study of the structure and function of the cell, especially the chromosomes. It includes routine analysis of G-Banded chromosomes, other cytogenetic banding techniques, as well as molecular cytogenetics such as fluorescent in situ...

, molecular genetics
Molecular genetics
Molecular genetics is the field of biology and genetics that studies the structure and function of genes at a molecular level. The field studies how the genes are transferred from generation to generation. Molecular genetics employs the methods of genetics and molecular biology...

, biochemical genetics, genomics
Genomics
Genomics is a discipline in genetics concerning the study of the genomes of organisms. The field includes intensive efforts to determine the entire DNA sequence of organisms and fine-scale genetic mapping efforts. The field also includes studies of intragenomic phenomena such as heterosis,...

, population genetics
Population genetics
Population genetics is the study of allele frequency distribution and change under the influence of the four main evolutionary processes: natural selection, genetic drift, mutation and gene flow. It also takes into account the factors of recombination, population subdivision and population...

, developmental genetics, clinical genetics, and genetic counseling
Genetic counseling
Genetic counseling or traveling is the process by which patients or relatives, at risk of an inherited disorder, are advised of the consequences and nature of the disorder, the probability of developing or transmitting it, and the options open to them in management and family planning...

. Genes can be the common factor of the qualities of most human-inherited traits. Study of human genetics can be useful as it can answer questions about human nature, understand the diseases and development of effective disease treatment, and understand genetics of human life.
Encyclopedia
Human genetics describes the study of inheritance as it occurs in human beings. Human genetics encompasses a variety of overlapping fields including: classical genetics
Classical genetics
Classical genetics consists of the technique and methodologies of genetics that predate the advent of molecular biology. A key discovery of classical genetics in eukaryotes was genetic linkage...

, cytogenetics
Cytogenetics
Cytogenetics is a branch of genetics that is concerned with the study of the structure and function of the cell, especially the chromosomes. It includes routine analysis of G-Banded chromosomes, other cytogenetic banding techniques, as well as molecular cytogenetics such as fluorescent in situ...

, molecular genetics
Molecular genetics
Molecular genetics is the field of biology and genetics that studies the structure and function of genes at a molecular level. The field studies how the genes are transferred from generation to generation. Molecular genetics employs the methods of genetics and molecular biology...

, biochemical genetics, genomics
Genomics
Genomics is a discipline in genetics concerning the study of the genomes of organisms. The field includes intensive efforts to determine the entire DNA sequence of organisms and fine-scale genetic mapping efforts. The field also includes studies of intragenomic phenomena such as heterosis,...

, population genetics
Population genetics
Population genetics is the study of allele frequency distribution and change under the influence of the four main evolutionary processes: natural selection, genetic drift, mutation and gene flow. It also takes into account the factors of recombination, population subdivision and population...

, developmental genetics, clinical genetics, and genetic counseling
Genetic counseling
Genetic counseling or traveling is the process by which patients or relatives, at risk of an inherited disorder, are advised of the consequences and nature of the disorder, the probability of developing or transmitting it, and the options open to them in management and family planning...

. Genes can be the common factor of the qualities of most human-inherited traits. Study of human genetics can be useful as it can answer questions about human nature, understand the diseases and development of effective disease treatment, and understand genetics of human life. This article describes only basic features of human genetics; for the genetics of disorders please see: Medical genetics
Medical genetics
Medical genetics is the specialty of medicine that involves the diagnosis and management of hereditary disorders. Medical genetics differs from Human genetics in that human genetics is a field of scientific research that may or may not apply to medicine, but medical genetics refers to the...

.


Genetic differences and inheritance patterns

Inheritance of traits for humans are based upon Gregor Mendel
Gregor Mendel
Gregor Johann Mendel was an Austrian scientist and Augustinian friar who gained posthumous fame as the founder of the new science of genetics. Mendel demonstrated that the inheritance of certain traits in pea plants follows particular patterns, now referred to as the laws of Mendelian inheritance...

's model of inheritance. Mendel deduced that inheritance depends upon discrete units of inheritance, called factors or genes.

Autosomal dominant inheritance

Autosomal traits are associated with a single gene on an autosome (non-sex chromosome)—they are called "dominant
Dominance
Dominance may refer to:* Dominance , an aspect of virtual inheritance in the C++ programming language* Dominance , in economics, the degree of inequality in market share distribution...

" because a single copy—inherited from either parent—is enough to cause this trait to appear. This often means that one of the parents must also have the same trait, unless it has arisen due to a new mutation. Examples of autosomal dominant traits and disorders are Huntington's disease
Huntington's disease
Huntington's disease, chorea, or disorder , is a neurodegenerative genetic disorder that affects muscle coordination and leads to cognitive decline and dementia. It typically becomes noticeable in middle age. HD is the most common genetic cause of abnormal involuntary writhing movements called chorea...

, and achondroplasia
Achondroplasia
Achondroplasia dwarfism occurs as a sporadic mutation in approximately 85% of cases or may be inherited in an autosomal dominant genetic disorder that is a common cause of dwarfism...

.

Autosomal recessive inheritance

Autosomal recessive traits is one pattern of inheritance for a trait, disease, or disorder to be passed on through families. For a recessive trait or disease to be displayed two copies of the trait or disorder needs to be presented. The trait or gene will be located on a non-sex chromosome. Because it takes two copies of a trait to display a trait, many people can unknowingly be carriers of a disease. From an evolutionary perspective, a recessive disease or trait can remain hidden for several generations before displaying the phenotype. Examples of autosomal recessive disorders are albinism
Albinism
Albinism is a congenital disorder characterized by the complete or partial absence of pigment in the skin, hair and eyes due to absence or defect of an enzyme involved in the production of melanin...

, Cystic Fibrosis
Cystic fibrosis
Cystic fibrosis is a recessive genetic disease affecting most critically the lungs, and also the pancreas, liver, and intestine...

, Tay-Sachs disease
Tay-Sachs disease
Tay–Sachs disease is an autosomal recessive genetic disorder...

.

X-linked and Y-linked inheritance

X-linked genes are found on the sex X chromosome. X-linked genes just like autosomal genes have both dominant and recessive types. Recessive X-linked disorders are rarely seen in females and usually only affect males. This is because males inherit their X chromosome and all X-linked genes will be inherited from the maternal side. Fathers only pass on their Y chromosome to their sons, so no X-linked traits will be inherited from father to son. Females express X-linked disorders when they are homozygous for the disorder and become carriers when they are heterozygous. X-linked dominant inheritance will show the same phenotype as a heterozygote and homozygote. Just like X-linked inheritance, there will be a lack of male-to-male inheritance, which makes it distinguishable from autosomal traits. One example of a X-linked trait is Coffin-Lowry syndrome
Coffin-Lowry syndrome
Coffin-Lowry syndrome is a genetic disorder that is X-linked dominant and which causes severe mental problems sometimes associated with abnormalities of growth, cardiac abnormalities, kyphoscoliosis, as well as auditory and visual abnormalities.-History:...

, which is caused by a mutation in ribosomal protein gene. This mutation results in skeletal, craniofacial abnormalities, mental retardation, and short stature.

X chromosomes in females undergo a process known as X inactivation. X inactivation is when one of the two X chromosomes in females is almost completely inactivated. It is important that this process occurs otherwise a woman would produce twice the amount of normal X chromosome proteins. The mechanism for X inactivation will occur during the embryonic stage. For people with disorders like trisomy X, where the genotype has three X chromosomes, X-inactivation will inactivate all X chromosomes until there is only one X chromosome active. X inactivation is not only limited to females, males with Klinefelter syndrome, who have an extra X chromosome, will also undergo X inactivation to have only one completely active X chromosome.

Y-linked inheritance occurs when a gene, trait, or disorder is transferred through the Y chromosome. Since Y chromosomes can only be found in males, Y linked traits are only passed on from father to son. The testis determining factor
Testis determining factor
Testis-determining factor is a general term for the gene that results in maleness in humans and some other species.Certain genes cause chemical reactions that result in the development of testes...

, which is located on the Y chromosome, determines the maleness of individuals. Besides the maleness inherited in the Y-chromosome there are no other found Y-linked characteristics.

Pedigrees

A pedigree
Pedigree chart
A pedigree chart is a diagram that shows the occurrence and appearance or phenotypes of a particular gene or organism and its ancestors from one generation to the next, most commonly humans, show dogs, and race horses....

 is a diagram showing the ancestral relationships and transmission of genetic traits over several generations in a family; square symbols are almost always used to represent males, whilst circles are used for females. Pedigrees are used to help detect many different genetic diseases. A pedigree can also be used to help determine the chances for a parent to produce an offspring with a specific trait. Four different traits can be identified by pedigree chart analysis: autosomal dominant, autosomal recessive, x-linked, or y-linked. Partial penetrance can be shown and calculated form pedigrees. Penetrance is the percentage expressed frequency with which individuals of a given genotype manifest at least some degree of a specific mutant phenotype associated with a trait. Inbreeding
Inbreeding
Inbreeding is the reproduction from the mating of two genetically related parents. Inbreeding results in increased homozygosity, which can increase the chances of offspring being affected by recessive or deleterious traits. This generally leads to a decreased fitness of a population, which is...

, the mating between closely related organisms of traits can clearly be seen on pedigree charts. Pedigree charts of royal families have a high degree of inbreeding, because it was customary and preferable for royalty to marry another member of royalty. Genetic counselors commonly use pedigrees to help couple determine if the parents will be able to produce healthy children.

Karyotype

A karyotype
Karyotype
A karyotype is the number and appearance of chromosomes in the nucleus of an eukaryotic cell. The term is also used for the complete set of chromosomes in a species, or an individual organism.p28...

 is a very useful tool in cytogenetics. A karyotype is picture of all the chromosomes in the metaphase
Metaphase
Metaphase, from the ancient Greek μετά and φάσις , is a stage of mitosis in the eukaryotic cell cycle in which condensed & highly coiled chromosomes, carrying genetic information, align in the middle of the cell before being separated into each of the two daughter cells...

 stage arranged according to length and centromere position. A karyotype can also be useful in clinical genetics, due to its ability to diagnose genetic disorders. On a normal karyotype, aneuploidy
Aneuploidy
Aneuploidy is an abnormal number of chromosomes, and is a type of chromosome abnormality. An extra or missing chromosome is a common cause of genetic disorders . Some cancer cells also have abnormal numbers of chromosomes. Aneuploidy occurs during cell division when the chromosomes do not separate...

 can be detected by clearly being able to observe any missing or extra chromosomes. Giemsa banding, g-banding, of the karyotype can be used to detect deletions, insertions
Insertion (genetics)
In genetics, an insertion is the addition of one or more nucleotide base pairs into a DNA sequence. This can often happen in microsatellite regions due to the DNA polymerase slipping...

, duplications, inversions, and translocations. G-banding will stain the chromosomes with light and dark bands unique to each chromosome. A FISH, fluorescent in situ hybridization
Fluorescent in situ hybridization
FISH is a cytogenetic technique developed by biomedical researchers in the early 1980s that is used to detect and localize the presence or absence of specific DNA sequences on chromosomes. FISH uses fluorescent probes that bind to only those parts of the chromosome with which they show a high...

, can be used to observe deletions, insertions, and translocations. FISH uses fluorescent probes to bind to specific sequences of the chromosomes that will cause the chromosomes to fluoresce a unique color.

Genomics

Genomics refers to the field of genetics concerned with structural and functional studies of the genome. A genome
Genome
In modern molecular biology and genetics, the genome is the entirety of an organism's hereditary information. It is encoded either in DNA or, for many types of virus, in RNA. The genome includes both the genes and the non-coding sequences of the DNA/RNA....

 is all the DNA contained within an organism or a cell including nuclear and mitochondrial DNA. The human genome
Human genome
The human genome is the genome of Homo sapiens, which is stored on 23 chromosome pairs plus the small mitochondrial DNA. 22 of the 23 chromosomes are autosomal chromosome pairs, while the remaining pair is sex-determining...

 is the total collection of genes in a human being contained in the human chromosome, composed of over three billion nucleotides. In April 2003, the Human Genome Project
Human Genome Project
The Human Genome Project is an international scientific research project with a primary goal of determining the sequence of chemical base pairs which make up DNA, and of identifying and mapping the approximately 20,000–25,000 genes of the human genome from both a physical and functional...

 was able to sequence all the DNA in the human genome, and to discover that the human genome was composed of around 20,000 protein coding genes.

Population genetics

Population genetics is the branch of evolutionary biology responsible for investigating processes that cause changes in allele and genotype frequencies in populations based upon Mendelian inheritance
Mendelian inheritance
Mendelian inheritance is a scientific description of how hereditary characteristics are passed from parent organisms to their offspring; it underlies much of genetics...

. Four different forces can influence the frequencies: natural selection
Natural selection
Natural selection is the nonrandom process by which biologic traits become either more or less common in a population as a function of differential reproduction of their bearers. It is a key mechanism of evolution....

, mutation
Mutation
In molecular biology and genetics, mutations are changes in a genomic sequence: the DNA sequence of a cell's genome or the DNA or RNA sequence of a virus. They can be defined as sudden and spontaneous changes in the cell. Mutations are caused by radiation, viruses, transposons and mutagenic...

, gene flow
Gene flow
In population genetics, gene flow is the transfer of alleles of genes from one population to another.Migration into or out of a population may be responsible for a marked change in allele frequencies...

 (migration), and genetic drift
Genetic drift
Genetic drift or allelic drift is the change in the frequency of a gene variant in a population due to random sampling.The alleles in the offspring are a sample of those in the parents, and chance has a role in determining whether a given individual survives and reproduces...

. A population can be defined as a group of interbreeding individuals and their offspring. For human genetics the populations will consist only of the human species. The Hardy-Weinberg principle
Hardy-Weinberg principle
The Hardy–Weinberg principle states that both allele and genotype frequencies in a population remain constant—that is, they are in equilibrium—from generation to generation unless specific disturbing influences are introduced...

 is a widely used principle to determine allelic and genotype frequencies.

Hardy-Weinberg principle

The Hardy-Weinberg principle states that when no evolution occurs in a population the allele and genotype frequencies do not change from one generation to the next. No evolution refers to no mutation, no gene flow, no natural selection, and no genetic drift. To be in equilibrium two more assumptions need to be made that random mating occurs and there are discrete, non-overlapping generations.

Mitochondrial DNA

In addition to nuclear DNA
Nuclear DNA
Nuclear DNA, nuclear deoxyribonucleic acid , is DNA contained within a nucleus of eukaryotic organisms. In mammals and vertebrates, nuclear DNA encodes more of the genome than the mitochondrial DNA and is composed of information inherited from two parents, one male, and one female, rather than...

, humans (like almost all eukaryotes) have mitochondrial DNA
Mitochondrial DNA
Mitochondrial DNA is the DNA located in organelles called mitochondria, structures within eukaryotic cells that convert the chemical energy from food into a form that cells can use, adenosine triphosphate...

. Mitochondria, the "power houses" of a cell, have their own DNA because they are descended from a proteobacterium
Proteobacteria
The Proteobacteria are a major group of bacteria. They include a wide variety of pathogens, such as Escherichia, Salmonella, Vibrio, Helicobacter, and many other notable genera....

 that merged with eukaryotic cells over 2 billion years ago—an assertion known as the endosymbiotic hypothesis. Mitochondria are inherited from one's mother, and its DNA is frequently used to trace maternal lines of descent (see mitochondrial Eve
Mitochondrial Eve
In the field of human genetics, Mitochondrial Eve refers to the matrilineal "MRCA" . In other words, she was the woman from whom all living humans today descend, on their mother's side, and through the mothers of those mothers and so on, back until all lines converge on one person...

). Mitochondrial DNA is only 16kb in length and encodes for 62 genes.

Genes and human characteristics

Genes are a fundamental unit of inheritance. Genes can be defined as a sequence of DNA in the genome that is required for production of a functional product. Genes have both minor and major effects on human characteristics. Human genes have become prominent in the nature versus nurture
Nature versus nurture
The nature versus nurture debate concerns the relative importance of an individual's innate qualities versus personal experiences The nature versus nurture debate concerns the relative importance of an individual's innate qualities ("nature," i.e. nativism, or innatism) versus personal experiences...

 debate.

Genes and behavior

Genes have a strong influence on human behavior. IQ is largely heritable
Inheritance of intelligence
The study of the heritability of IQ investigates the relative importance of genetics and environment for variation in intelligence quotient in a population...

. However, this has been questioned. The stance that humans inherit substantial behavioral characteristics is called psychological nativism
Psychological nativism
In the field of psychology, nativism is the view that certain skills or abilities are 'native' or hard wired into the brain at birth. This is in contrast to empiricism, the 'blank slate' or tabula rasa view, which states that the brain has inborn capabilities for learning from the environment but...

, compared to the stance that human behavior and culture are virtually entirely constructed (tabula rasa
Tabula rasa
Tabula rasa is the epistemological theory that individuals are born without built-in mental content and that their knowledge comes from experience and perception. Generally proponents of the tabula rasa thesis favour the "nurture" side of the nature versus nurture debate, when it comes to aspects...

).

In the early 20th century, eugenics
Eugenics
Eugenics is the "applied science or the bio-social movement which advocates the use of practices aimed at improving the genetic composition of a population", usually referring to human populations. The origins of the concept of eugenics began with certain interpretations of Mendelian inheritance,...

 was policy in parts of the United States and Europe. The goal was to reduce or eliminate traits that were considered undesirable. One form of eugenics was compulsory sterilization
Compulsory sterilization
Compulsory sterilization also known as forced sterilization programs are government policies which attempt to force people to undergo surgical sterilization...

 of people deemed mentally unfit. Hitler's eugenics programs turned social consciousness
Social consciousness
Social consciousness is consciousness shared within a society. It can also be defined as social awareness; to be aware of the problems that different societies and communities face on a day-to-day basis; to be conscious of the difficulties and hardships of society.- Theory :Many studies have been...

 against the practice, and psychological nativism became associated with racism and sexism.

Evolutionary psychology

Evolutionary psychology
Evolutionary psychology
Evolutionary psychology is an approach in the social and natural sciences that examines psychological traits such as memory, perception, and language from a modern evolutionary perspective. It seeks to identify which human psychological traits are evolved adaptations, that is, the functional...

 explains many human behaviors as more or less moderated by genes that evolved in the hunter-gatherer stage of human cultural development. See for example Stockholm syndrome
Stockholm syndrome
In psychology, Stockholm Syndrome is an apparently paradoxical psychological phenomenon wherein hostages express empathy and have positive feelings towards their captors, sometimes to the point of defending them...

.

Human traits with simple inheritance patterns

Dominant Recessive References
Widow's peak
Widow's peak
A widow's peak is a distinct point in the hairline in the center of the forehead. This hair anomaly is a result of a lower-than-usual position of the intersection of the bilateral periorbital fields of hair-growth suppression on the forehead.-Definition:...

straight hair line
Facial Dimples
Dimple
A dimple is a small natural indentation in the flesh on a part of the human body, most notably in the cheek or on the chin.-More about dimples:...

 **
No Facial Dimples
Able to taste PTC
Phenylthiocarbamide
Phenylthiocarbamide, also known as PTC, or phenylthiourea,is an organosulfur thiourea containing a phenyl ring.It has the unusual property that it either tastes very bitter or is virtually tasteless, depending on the genetic makeup of the taster...

Unable to taste PTC
Phenylthiocarbamide
Phenylthiocarbamide, also known as PTC, or phenylthiourea,is an organosulfur thiourea containing a phenyl ring.It has the unusual property that it either tastes very bitter or is virtually tasteless, depending on the genetic makeup of the taster...

Unattached earlobe Attached earlobe
Clockwise hair direction (left to right) Counter-Clockwise hair direction (right to left)
Cleft chin
Cleft chin
The terms cleft chin, chin cleft, butt chin, superhero chin, dimple chin, or a chin dimple refer to a dimple on the chin. It is a Y-shaped fissure on the chin with an underlying bony peculiarity...

smooth chin
Color Vision Color blindness
Color blindness
Color blindness or color vision deficiency is the inability or decreased ability to see color, or perceive color differences, under lighting conditions when color vision is not normally impaired...

straight nose turned up nose
Ability to roll tongue (Able to hold tongue in a U shape) No ability to roll tongue
straight Pinkies Crooked Pinkies
Straight Thumb
Thumb
The thumb is the first digit of the hand. When a person is standing in the medical anatomical position , the thumb is the lateral-most digit...

Hitchhiker's Thumb
Freckles No Freckles
Wet-type earwax
Earwax
Earwax, also known by the medical term cerumen, is a yellowish waxy substance secreted in the ear canal of humans and other mammals. It protects the skin of the human ear canal, assists in cleaning and lubrication, and also provides some protection from bacteria, fungi, insects and water...

Dry-type earwax
Earwax
Earwax, also known by the medical term cerumen, is a yellowish waxy substance secreted in the ear canal of humans and other mammals. It protects the skin of the human ear canal, assists in cleaning and lubrication, and also provides some protection from bacteria, fungi, insects and water...

Curly Hair Straight Hair
A and B blood type O blood type
Abundant body hair Little body hair
Broad Lips Slender Lips
Broad nose narrow nose
High blood pressure Low blood pressure
Webbed Fingers Normal finger
dominant left thumb dominant right Thumb
Nearsightedness Normal vision
Mid digit Hair no mid digit hair
Morton's toe
Morton's toe
Morton's toe is the common term for the condition of a shortened first metatarsal in relation to the second metatarsal. It is a type of brachymetatarsia. This promotes an anterior position of the second metatarsal-phalangeal joint in relation to the hallux...

hammer toe
Hallux
In tetrapods, the hallux is the innermost toe of the foot. Despite its name it may not be the longest toe on the foot of some individuals...

Hair on back of hand no manus hair
Roman nose
Roman Nose
Roman Nose, a.k.a. Hook Nose , was a Native American of the Northern Cheyenne, and possibly the greatest and most influential warrior during the Plains Indian War of the 1860s...

no prominent bridge
short statue tall statue
Magrines none
large eyes Small eyes
tone deafness
Tone deafness
Tone deafness is the lack of relative pitch, or the inability to distinguish between musical notes that is not due to the lack of musical training or education...

normal hearing
Darker hair Lighter hair
normal night vision Night blindness
different colour temple
Temple (anatomy)
Temple indicates the side of the head behind the eyes. The bone beneath is the temporal bone as well as part of the sphenoid bone.-Anatomy:Cladists classify land vertebrates based on the presence of an upper hole, a lower hole, both, or neither in the cover of dermal bone which formerly covered the...

 highlights
same colour temple
Temple (anatomy)
Temple indicates the side of the head behind the eyes. The bone beneath is the temporal bone as well as part of the sphenoid bone.-Anatomy:Cladists classify land vertebrates based on the presence of an upper hole, a lower hole, both, or neither in the cover of dermal bone which formerly covered the...

 highlights
Clubbed thumb
Clubbed thumb
A clubbed thumb is a term used to describe the genetic clubbing of one or both thumbs. It is characterized by a short, fat thumb that is round. The thumb nail is wide and short...

regular size
oval shaped face square shape
separated eyebrows Joined eyebrow
long eyelashes short eyelashes
Roll tongue unable to roll
Marfan's syndrome normal body proportions
Huntington disease no nerve damage
normal mucus lining Cystic fibrosis
Cystic fibrosis
Cystic fibrosis is a recessive genetic disease affecting most critically the lungs, and also the pancreas, liver, and intestine...

Photic sneeze reflex
Photic sneeze reflex
The photic sneeze reflex is a condition of uncontrollable sneezing in response to numerous stimuli, such as looking at bright lights or periocular injection...

no ACHOO reflex
forged chin Receding chin
White Forelock Dark Forelock
Straight thumb curved thumb
ability to move ears can't move ears
Dwarfism
Dwarfism
Dwarfism is short stature resulting from a medical condition. It is sometimes defined as an adult height of less than 4 feet 10 inches  , although this definition is problematic because short stature in itself is not a disorder....

standard height
Human height
Human height is the distance from the bottom of the feet to the top of the head in a human body standing erect.When populations share genetic background and environmental factors, average height is frequently characteristic within the group...

situs solitus
Situs solitus
Situs solitus refers to the normal position of thoracic and abdominal organs. Anatomically, this means that the heart is on the left with the pulmonary atrium on the right and the systemic atrium on the left along with the cardiac apex...

 left-sided heart & stomach
Situs inversus
Situs inversus
Situs inversus is a congenital condition in which the major visceral organs are reversed or mirrored from their normal positions. The normal arrangement is known as situs solitus...

 right-sided heart & stomach
Ligamentous angustus Ligamentous Laxity
Ligamentous Laxity
Ligamentous laxity is a term given to describe "loose ligaments."In a 'normal' body, ligaments are naturally tight in such a way that the joints are restricted to 'normal' ranges of motion. This creates normal joint stability...

normal mental ablitities Tay–Sachs disease
ability to eat sugar Galactosemia
Galactosemia
Galactosemia is a rare genetic metabolic disorder that affects an individual's ability to metabolize the sugar galactose properly. Although the sugar lactose can metabolize to galactose, galactosemia is not related to and should not be confused with lactose intolerance...

Ehlers–Danlos syndrome strong collagen
regular muscle tissue Duchenne muscular dystrophy
Duchenne muscular dystrophy
Duchenne muscular dystrophy is a recessive X-linked form of muscular dystrophy, which results in muscle degeneration, difficulty walking, breathing, and death. The incidence is 1 in 3,000 boys. Females and males are affected, though females are rarely affected and are more often carriers...

High cholestrol Low cholestrol
Darwin's tubercle
Darwin's tubercle
Darwin's tubercle is a congenital ear condition which often presents as a thickening on the helix at the junction of the upper and middle thirds. The feature is present in approximately 10.4% of the population...

curved ear Helix
Almond eye shape Rounded eye Shape
two palmar tendons three palmar tendons
no urinal colouration Beeturia
Beeturia
Beeturia is passing of red or pink urine after eating beets. It affects 10-14% of the population. While some believe it to be an autosomal recessive trait, it has been shown that individuals differ over time in having beeturia. Beeturia can appear and disappear in individuals...


See also

  • Human evolutionary genetics
    Human evolutionary genetics
    Human evolutionary genetics studies how one human genome differs from the other, the evolutionary past that gave rise to it, and its current effects. Differences between genomes have anthropological, medical and forensic implications and applications...

  • Human genome
    Human genome
    The human genome is the genome of Homo sapiens, which is stored on 23 chromosome pairs plus the small mitochondrial DNA. 22 of the 23 chromosomes are autosomal chromosome pairs, while the remaining pair is sex-determining...

  • Genetic genealogy
    Genetic genealogy
    Genetic genealogy is the application of genetics to traditional genealogy. Genetic genealogy involves the use of genealogical DNA testing to determine the level of genetic relationship between individuals.-History:...

  • Human genetic clustering
    Human genetic clustering
    Human genetic clustering analysis uses mathematical cluster analysis of the degree of similarity of genetic data between individuals and groups to infer population structures and assign individuals to groups that often correspond with their self-identified geographical ancestry...

  • Genealogical DNA test
    Genealogical DNA test
    A genealogical DNA test examines the nucleotides at specific locations on a person's DNA for genetic genealogy purposes. The test results are not meant to have any informative medical value and do not determine specific genetic diseases or disorders ; they are intended only to give genealogical...

  • List of Mendelian traits in humans
  • Primatology
    Primatology
    Primatology is the scientific study of primates. It is a diverse discipline and researchers can be found in academic departments of anatomy, anthropology, biology, medicine, psychology, veterinary sciences and zoology, as well as in animal sanctuaries, biomedical research facilities, museums and zoos...

  • HAX1
    HAX1
    HCLS1-associated protein X-1 is a protein that in humans is encoded by the HAX1 gene.-Severe congenital neutropenia:Homozygous mutations in HAX1 are associated with autosomal recessive severe congenital neutropenia, also known as Kostmann syndrome....


  • Y-chromosome haplogroups by populations
    Y-chromosome haplogroups by populations
    The following articles are lists of human Y-chromosome DNA haplogroups found in populations and various ethnic groups by regions or continents around the world based on relevant studies, and the samples have been taken from individuals identified by linguistic designation.General*Y-DNA haplogroups...

  • List of haplogroups of historical and famous figures
  • Genetic history of indigenous peoples of the Americas
  • Genetic history of the British Isles
    Genetic history of the British Isles
    The genetic history of the British Isles is the subject of research within the larger field of human population genetics. It has developed in parallel with DNA testing technologies capable of identifying genetic similarities and differences between populations...

  • Archaeogenetics of the Near East
    Archaeogenetics of the Near East
    The archaeogenetics of the Near East involves the study of aDNA or ancient DNA, identifying haplogroups and haplotypes of ancient skeletal remains from both YDNA and mtDNA for populations of the Ancient Near East The archaeogenetics of the Near East involves the study of aDNA or ancient DNA,...

  • Genetics and archaeogenetics of South Asia
    Genetics and archaeogenetics of South Asia
    The study of the genetics and archaeogenetics of the ethnic groups of South Asia aims at uncovering these groups' genetic history. The geographic position of India makes Indian populations important for the study of the early dispersal of all human populations on the Eurasian continent.The Indian...

  • Genetic history of Europe
    Genetic history of Europe
    The genetic history of Europe can be inferred from the patterns of genetic diversity across continents and time. The primary data to develop historical scenarios coming from sequences of mitochondrial, Y-chromosome and autosomal DNA from modern populations and if available from ancient DNA...

  • Genetic history of Italy
    Genetic history of Italy
    During prehistory Italy was populated by different but very similar Indo-European groups, later collectively listed amongst the Ancient peoples of Italy, of whom the Italic one was predominant....

  • Race and genetics


External links




The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK