Aarskog syndrome is caused by a change in a gene, most often the FGD1 gene on the X chromosome, and not by anything a parent did before or during pregnancy.
FGD1 helps direct how bones, muscles, and connective tissue form during early development, so a change in it affects height, facial features, hands, and genital development. The condition follows an X-linked recessive pattern, which is why boys are affected more often and more noticeably, and why a mother who carries one altered copy may have only mild signs such as short fingers or a widow's peak. Many people who fit the clinical picture have no FGD1 change found on genetic testing, so other genes are likely involved and a negative test does not rule out the diagnosis. A clinical geneticist can confirm the diagnosis, order the right test, and explain what the result means for future pregnancies. Day to day, the practical work is steady growth monitoring plus regular dental, eye, and orthopedic checks.
Where it comes from
Common questions
What causes Aarskog syndrome?
Aarskog syndrome, also called Aarskog-Scott syndrome, is a genetic condition present from birth. In most identified cases it comes from a change in the FGD1 gene on the X chromosome, which helps direct how bones, muscles, and connective tissue form before birth. The pattern is usually X-linked recessive, so boys are affected more often and more noticeably, while girls who carry one altered copy may have mild features such as short fingers or a widow's peak. Many people with the diagnosis have no FGD1 change found on testing, so other genes likely play a role. It is not caused by diet, stress, injury, or anything done during pregnancy.