How is Aarskog syndrome inherited?
Aarskog syndrome is typically inherited in an X-linked pattern. The 'X' chromosome is a sex chromosome. The 'Y' chromosome is the other sex chromosome. Males usually have one X chromosome and one Y chromosome. Females usually have two X chromosomes. The FGD1 gene for Aarskog syndrome is located on the X chromosome. Because males only have one X chromosome and therefore one FGD1 gene, if this gene has a mutation, the male is affected with Aarskog syndrome. Because females have two X chromosomes, if one of their FGD1 genes has a mutation, they are known as heteozygotes and may not have symptoms of Aarskog. However, some female heterozygotes of Aarskog syndrome have mild features of the condition.
Even though most cases of Aarskog syndrome are X-linked, in rare cases it can run in the family in a different ways, both autosomal dominant and recessive patterns of inheritance, but the genetic cause in these cases currently remains unknown.
It is important to take into account family history when discussing inheritance patterns. A genetic counselor or medical geneticist can help determine the way the condition is being passed down in a particular family. A medical geneticists can be found by asking your doctor for a referral or looking on the American College of Medical Geneticists website. Genetic counselors can be found on the National Society of Genetic Counselors website.
Xu, M., Qi, M., Zhou, H., Qui, H., et al. (2010). Familial syndrome resembling Aarskog syndrome. American Journal of Medical Genetics. Part A, 152A, 2017?2022. PMID: 20607856