Brachydactyly
Encyclopedia
Brachydactyly is a medical term which literally means "shortness of the fingers and toes" (digits). The shortness is relative to the length of other long bone
s and other parts of the body. Brachydactyly is an inherited, usually dominant trait. It most often occurs as an isolated dysmelia
, but can also occur with other anomalies as part of many congenital syndrome
s.
Nomogram
s for normal values of finger length as a ratio to other body measurements have been published. In clinical genetics
the most commonly used index of digit length is the dimensionless ratio of the length of the 3rd (middle) finger to the hand length. Both are expressed in the same units (centimeters, for example) and are measured in an open hand from the fingertip to the principal creases where the finger joins the palm and where the palm joins the wrist. A nomogram can be found in the Appendix of Jones, ed. Smith's Recognizable Patterns of Human Malformation, 5th edition, Philadelphia: Saunders (1997).
, Cushing syndrome, Rubinstein-Taybi syndrome
, etc.), brachydactyly is a minor feature compared to the other anomalies or problems comprising the syndrome.
Bone
Bones are rigid organs that constitute part of the endoskeleton of vertebrates. They support, and protect the various organs of the body, produce red and white blood cells and store minerals. Bone tissue is a type of dense connective tissue...
s and other parts of the body. Brachydactyly is an inherited, usually dominant trait. It most often occurs as an isolated dysmelia
Dysmelia
Dysmelia is a congenital disorder referring to the limbs. -Types:Dysmelia can refer to*missing limbs: amelia, oligodactyly, congenital amputation...
, but can also occur with other anomalies as part of many congenital syndrome
Syndrome
In medicine and psychology, a syndrome is the association of several clinically recognizable features, signs , symptoms , phenomena or characteristics that often occur together, so that the presence of one or more features alerts the physician to the possible presence of the others...
s.
Nomogram
Nomogram
A nomogram, nomograph, or abac is a graphical calculating device developed by P.E. Elyasberg, a two-dimensional diagram designed to allow the approximate graphical computation of a function: it uses a coordinate system other than Cartesian coordinates...
s for normal values of finger length as a ratio to other body measurements have been published. In clinical genetics
Genetics
Genetics , a discipline of biology, is the science of genes, heredity, and variation in living organisms....
the most commonly used index of digit length is the dimensionless ratio of the length of the 3rd (middle) finger to the hand length. Both are expressed in the same units (centimeters, for example) and are measured in an open hand from the fingertip to the principal creases where the finger joins the palm and where the palm joins the wrist. A nomogram can be found in the Appendix of Jones, ed. Smith's Recognizable Patterns of Human Malformation, 5th edition, Philadelphia: Saunders (1997).
Types
There are several types of Brachydactyly:| Type | OMIM | Gene | Locus Locus (genetics) In the fields of genetics and genetic computation, a locus is the specific location of a gene or DNA sequence on a chromosome. A variant of the DNA sequence at a given locus is called an allele. The ordered list of loci known for a particular genome is called a genetic map... |
Also known as/Description >- |Type A1, BDA1 |
IHH IHH Indian hedgehog homolog , also known as IHH, is a protein which in humans is encoded by the IHH gene.-Function:The Indian Hedgehog protein is one of three proteins in the mammalian hedgehog family, the others being desert hedgehog and Sonic hedgehog... BDA1B |
5p13.3-p13.2, 2q33-q35 | phalanges Phalanx bones In anatomy, phalanx bones are those that form the fingers and toes. In primates such as humans and monkeys, the thumb and big toe have two phalanges, while the other fingers and toes consist of three. Phalanges are classified as long bones.The phalanges do not have individual names... , Extra carpal bones, Hypoplastic Hypoplasia Hypoplasia is underdevelopment or incomplete development of a tissue or organ. Although the term is not always used precisely, it properly refers to an inadequate or below-normal number of cells. Hypoplasia is similar to aplasia, but less severe. It is technically not the opposite of hyperplasia... or absent ulna Ulna The ulna is one of the two long bones in the forearm, the other being the radius. It is prismatic in form and runs parallel to the radius, which is shorter and smaller. In anatomical position The ulna is one of the two long bones in the forearm, the other being the radius. It is prismatic in form... and Short metacarpal bones. >- |Type A2, BDA2 |
BMPR1B BMPR1B Bone morphogenetic protein receptor type-1B also known as CDw293 is a protein that in humans is encoded by the BMPR1B gene.- Function :... GDF5 GDF5 Growth/differentiation factor 5 is a protein that in humans is encoded by the GDF5 gene.Growth differentiation factor 5 is a protein belonging to the transforming growth factor beta superfamily that is expressed in the developing central nervous system, and has a role in skeletal and joint... |
20q11.2, 4q23-q24 | >- | >- | >- | >- | >- | >- | ROR2 ROR2 Tyrosine-protein kinase transmembrane receptor ROR2 also known as neurotrophic tyrosine kinase, receptor-related 2, is a protein that in humans is encoded by the ROR2 gene located on position 9 of the long arm of chromosome 9. This protein is responsible for aspects of bone and cartilage growth. It... |
9q22 | >- | GDF5 GDF5 Growth/differentiation factor 5 is a protein that in humans is encoded by the GDF5 gene.Growth differentiation factor 5 is a protein belonging to the transforming growth factor beta superfamily that is expressed in the developing central nervous system, and has a role in skeletal and joint... |
20q11.2 | >- | HOXD13 HOXD13 Homeobox protein Hox-D13 is a protein that in humans is encoded by the HOXD13 gene.This gene belongs to the homeobox family of genes. The homeobox genes encode a highly conserved family of transcription factors that play an important role in morphogenesis in all multicellular organisms... |
2q31-q32 | >- | HOXD13 HOXD13 Homeobox protein Hox-D13 is a protein that in humans is encoded by the HOXD13 gene.This gene belongs to the homeobox family of genes. The homeobox genes encode a highly conserved family of transcription factors that play an important role in morphogenesis in all multicellular organisms... |
2q31-q32 | >- | ROR2 ROR2 Tyrosine-protein kinase transmembrane receptor ROR2 also known as neurotrophic tyrosine kinase, receptor-related 2, is a protein that in humans is encoded by the ROR2 gene located on position 9 of the long arm of chromosome 9. This protein is responsible for aspects of bone and cartilage growth. It... HOXD13 HOXD13 Homeobox protein Hox-D13 is a protein that in humans is encoded by the HOXD13 gene.This gene belongs to the homeobox family of genes. The homeobox genes encode a highly conserved family of transcription factors that play an important role in morphogenesis in all multicellular organisms... |
9q22, 2q31-q32 | >- | 5p13.3-p13.2 | >- |
Other syndromes
In the above brachydactyly syndromes, short digits are the most prominent of the anomalies, but in many other syndromes (Down syndromeDown syndrome
Down syndrome, or Down's syndrome, trisomy 21, is a chromosomal condition caused by the presence of all or part of an extra 21st chromosome. It is named after John Langdon Down, the British physician who described the syndrome in 1866. The condition was clinically described earlier in the 19th...
, Cushing syndrome, Rubinstein-Taybi syndrome
Rubinstein-Taybi syndrome
Rubinstein-Taybi Syndrome , also known as broad thumb-hallux syndrome or Rubinstein syndrome, is a condition characterized by short stature, moderate to severe learning difficulties, distinctive facial features, and broad thumbs and first toes. Other features of the disorder vary among affected...
, etc.), brachydactyly is a minor feature compared to the other anomalies or problems comprising the syndrome.