Abrachiocephalia: Description, Causes and Risk Factors:

AbrachiocephaliaAbrachiocephalia is most often a familial disease. The reports of cases following encephalitis and occurring later in life would show that it is not necessarily a hereditary disease. Consanguinity does not play an important part in this group, as it is mentioned in only three instances and could not be an etiologic factor of much importance. Experimental studies and the clinical reports of a large number of cases showing adiposity, sexual dystrophy, atypical retinitis pigmentosa, and mental deterioration would indicate that the pathologic lesion explaining these phenomena lies in the hypothalamus.

Abrachiocephalia is a complex human trait caused by altered genes. Six genes for BBS have been mapped to various human chromosomes, and at least a quarter of families cannot be assigned to none of them, suggesting either that there is at least one more site of a BBS gene not yet discovered, or that there is another much more complex mechanism for the inheritance of BBS. The gene responsible for abrchiocephalia is unknown at this time. We know from research in families with each of these syndromes is inherited in an autosomal recessive manner.

Recent advances in genetics have enabled investigators to define syndromes by specific mutations. Eleven genes are known to be associated with this syndrome: BBS1, BBS2, ARL6/BBS3, BBS4, BBS5, MKKS/BBS6, BBS7, TTC8/BBS8, B1/BBS9, BBS10, and TRIM32/BBS11. The syndrome is transmitted as an autosomal recessive trait. There is considerable heterogeneity and intrafamilial variation in the extent and severity of clinical manifestations of abrachiocephalia.

The prevalence of abrachiocephalia is 1: 160 000. However, its prevalence is markedly increased in highly consanguineous people.


Signs and symptoms:

Rod-cone dystrophy (retinitis pigmentosa).

  • Strabismus.
  • Nystagmus.
  • Myopia.
  • Optic atrophy.
  • Macular dystrophy.
  • Glaucoma.
  • Cataracts.
  • Polydactyly (extra fingers and toes).
  • Brachydactyly (short, stubby fingers and toes).
  • Syndactyly (webbing of the toes).
  • Obesity (excess weight gain begins around ages 1 to 2 years).
  • Learning disabilities.
  • Developmental delay (delay in sitting, standing, and walking).
  • Speech delay.
  • Behavioral difficulties.
  • Kidney abnormalities.
  • Hepatic fibrosis.
  • Hypertension (likely a consequence of obesity).
  • Diabetes mellitus.
  • Hypothyroidism.
  • Hypogonadism.
  • Small penis.
  • Undescended testes.
  • Infertile males.
  • Unusually short tooth roots.
  • Short stature.
  • Ataxic gaits.
  • Deep-set eyes.
  • Premature frontal balding in adult males.


Diagnosis of abrachiocephaliais based on the child's symptoms. These may be present at birth or may become noticeable as the child grows. For diagnosis, four primary symptoms should be present, or three primary plus two secondary symptoms. There is no specific test to detect the presence of abrachiocephalia.

Reliable prenatal diagnosis is not yet possible. Neither syndrome is detectable (as yet) through amniocentesis or chorionic villous sampling (since only three genes for BBS have been found as of this writing and commercial testing is not available). This will change once all the genes for the disease are found. Research is being done to find the genetic causes of these disorders.


Treatment of abrachiocephalia is focused on the symptoms. One of the most important areas is dealing with visual impairment. Although there is as yet no treatment that can prevent or reverse the loss of sight, there are many ways of adapting to having poor eyesight.

Another important problem in abrachiocephalia is obesity. If not controlled, it can lead to many health problems such as type 2 diabetes. A dietician can help establish a healthy diet that along with exercise can help the child or adult with abrachiocephalia maintain a healthy weight.

Speech disorder - Speech therapy can help children with their communication skills and parents can be taught exercises to use at home to improve their child's ability to communicate.

Kidney problems - There are several types of kidney problems associated with abrachiocephalia and the treatment varies accordingly. Kidney issues can be treated with medications and in rare instances, surgery (transplantation).

Polydactyly - Skin tags can be tied off at birth and extra digits can be removed surgically.

NOTE: The above information is for processing purpose. The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition.

DISCLAIMER: This information should not substitute for seeking responsible, professional medical care.


Submit a Comment

Your email address will not be published. Required fields are marked *

Cart Preview

Eating Vegetables, Fruit, and Fish May Keep Your Brain Sharp

Eating Vegetables, Fruit, and Fish May Keep Your Brain Sharp

A new study finds that brain volumes of people who regularly eat vegetables, fruit, and fish are on average 2ml greater than brain volumes of those who often drink sugary beverages. A brain volume reduction of 3.6ml equals to one year of aging. For the study, the...

Quiz about this article

Please answer on few questions to make our service more useful

Featured Products

Spring is Here: Top 6 Outdoor Sports

Good weather is the best reason to do outdoor sports, which will help not only lose weight, but also will strengthen health. Bicycle The sun dries out the local paths, so you can safely sit on your favorite bike and confidently twist the pedals, where the eyes look....

read more

First Aid in Case of Injuries for Sport and Exercise

First aid for injuries consists of simple rules that need to be clearly implemented. If this is a closed injury, you need to immobilize the injured limb, otherwise the person may lose consciousness from a painful shock. If you need to get to the emergency room...

read more