Rs6313
Encyclopedia
In genetics
, rs6313 also called T102C or C102T is a gene variation—a single nucleotide polymorphism
(SNP)—in the human HTR2A gene
that codes for the 5-HT2A receptor.
The SNP is a synonymous substitution
located in exon 1 of the gene where it is involved in coding the 34th amino acid
as serine
.
As 5-HT2A is a neuroreceptor the SNP has been investigated in connection with brain functions and neuropsychiatric disorders, and it is perhaps the most investigated SNP for its gene.
Two other SNPs in HTR2A have also received much attention: rs6311
and His452Tyr (rs6314).
A less well investigated SNP of this gene is rs7997012
.
Meta-analyses seem to indicate that the SNP is not directly associated with schizophrenia
,
not with Alzheimer's Disease
,
and two initial studies seem to indicate that it is not associated with Parkinson's Disease
.
There have been multiple studies of the effect of the SNP on clozapine
treatment response in schizophrenia
.
A meta-analysis published in 1998 found an association.
These may or may not find a significant association, that will need to be replicated in further studies before any major conclussion is attempted.
Examples of individual studies are:
A genetic study has found higher extraversion personality score among borderline personality disorder
patients for the C-allele
.
Another study found a slight association with novelty seeking
among Italian mood disorder
patients,
whereas a German study noted association with the trait "reward dependence
".
A Chinese study found no association with suicidal behavior.
Furthermore, individual studies indicate that the SNP may be associated with rheumatoid arthritis
and not likely with the fibromyalgia syndrome.
One study implicated the C-allele in visual and auditory hallucination
s in Late-onset Alzheimer's Disease.
Genetics
Genetics , a discipline of biology, is the science of genes, heredity, and variation in living organisms....
, rs6313 also called T102C or C102T is a gene variation—a single nucleotide polymorphism
Single nucleotide polymorphism
A single-nucleotide polymorphism is a DNA sequence variation occurring when a single nucleotide — A, T, C or G — in the genome differs between members of a biological species or paired chromosomes in an individual...
(SNP)—in the human HTR2A gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
that codes for the 5-HT2A receptor.
The SNP is a synonymous substitution
Synonymous substitution
A synonymous substitution is the evolutionary substitution of one base for another in an exon of a gene coding for a protein, such that the produced amino acid sequence is not modified. Synonymous substitutions and mutations affecting noncoding DNA are collectively known as silent mutations...
located in exon 1 of the gene where it is involved in coding the 34th amino acid
Amino acid
Amino acids are molecules containing an amine group, a carboxylic acid group and a side-chain that varies between different amino acids. The key elements of an amino acid are carbon, hydrogen, oxygen, and nitrogen...
as serine
Serine
Serine is an amino acid with the formula HO2CCHCH2OH. It is one of the proteinogenic amino acids. By virtue of the hydroxyl group, serine is classified as a polar amino acid.-Occurrence and biosynthesis:...
.
As 5-HT2A is a neuroreceptor the SNP has been investigated in connection with brain functions and neuropsychiatric disorders, and it is perhaps the most investigated SNP for its gene.
Two other SNPs in HTR2A have also received much attention: rs6311
Rs6311
In genetics rs6311 is a gene variation—a single nucleotide polymorphism —in the human HTR2A gene that codes for the 5-HT2A receptor. 5-HT2A is neuroreceptor, and several scientific studies have investigated the effect of the genetic variation on personality, e.g., personality traits measured with...
and His452Tyr (rs6314).
A less well investigated SNP of this gene is rs7997012
Rs7997012
In genetics, rs7997012 is a gene variation—a single nucleotide polymorphism —in intron 2 of the human HTR2A gene that codes for the 5-HT2A receptor.The SNP varies between adenine and guanine DNA bases with the G-allele being most frequent....
.
Meta-analyses seem to indicate that the SNP is not directly associated with schizophrenia
Schizophrenia
Schizophrenia is a mental disorder characterized by a disintegration of thought processes and of emotional responsiveness. It most commonly manifests itself as auditory hallucinations, paranoid or bizarre delusions, or disorganized speech and thinking, and it is accompanied by significant social...
,
not with Alzheimer's Disease
Alzheimer's disease
Alzheimer's disease also known in medical literature as Alzheimer disease is the most common form of dementia. There is no cure for the disease, which worsens as it progresses, and eventually leads to death...
,
and two initial studies seem to indicate that it is not associated with Parkinson's Disease
Parkinson's disease
Parkinson's disease is a degenerative disorder of the central nervous system...
.
There have been multiple studies of the effect of the SNP on clozapine
Clozapine
Clozapine is an antipsychotic medication used in the treatment of schizophrenia, and is also used off-label in the treatment of bipolar disorder. Wyatt. R and Chew...
treatment response in schizophrenia
Schizophrenia
Schizophrenia is a mental disorder characterized by a disintegration of thought processes and of emotional responsiveness. It most commonly manifests itself as auditory hallucinations, paranoid or bizarre delusions, or disorganized speech and thinking, and it is accompanied by significant social...
.
A meta-analysis published in 1998 found an association.
Individual studies
Many individual studies investigate possible effects of the polymorphism on, say, a personality trait or a disorder.These may or may not find a significant association, that will need to be replicated in further studies before any major conclussion is attempted.
Examples of individual studies are:
A genetic study has found higher extraversion personality score among borderline personality disorder
Borderline personality disorder
Borderline personality disorder is a personality disorder described as a prolonged disturbance of personality function in a person , characterized by depth and variability of moods.The disorder typically involves unusual levels of instability in mood; black and white thinking, or splitting; the...
patients for the C-allele
Allele
An allele is one of two or more forms of a gene or a genetic locus . "Allel" is an abbreviation of allelomorph. Sometimes, different alleles can result in different observable phenotypic traits, such as different pigmentation...
.
Another study found a slight association with novelty seeking
Novelty seeking
In psychology, novelty seeking is a personality trait.It is measured in the Tridimensional Personality Questionnaire as well as the later version Temperament and Character Inventory.NS has been suggested to be related to low dopaminergic activity....
among Italian mood disorder
Mood disorder
Mood disorder is the term designating a group of diagnoses in the Diagnostic and Statistical Manual of Mental Disorders classification system where a disturbance in the person's mood is hypothesized to be the main underlying feature...
patients,
whereas a German study noted association with the trait "reward dependence
Reward dependence
In psychology, Reward Dependence is a moderately heritable personality trait which is stable throughout life. It is an inherited neurophysiological mechanism that drives our perception of the environment and society...
".
A Chinese study found no association with suicidal behavior.
Furthermore, individual studies indicate that the SNP may be associated with rheumatoid arthritis
Rheumatoid arthritis
Rheumatoid arthritis is a chronic, systemic inflammatory disorder that may affect many tissues and organs, but principally attacks synovial joints. The process produces an inflammatory response of the synovium secondary to hyperplasia of synovial cells, excess synovial fluid, and the development...
and not likely with the fibromyalgia syndrome.
One study implicated the C-allele in visual and auditory hallucination
Hallucination
A hallucination, in the broadest sense of the word, is a perception in the absence of a stimulus. In a stricter sense, hallucinations are defined as perceptions in a conscious and awake state in the absence of external stimuli which have qualities of real perception, in that they are vivid,...
s in Late-onset Alzheimer's Disease.