Aarskog syndrome is a rare genetic condition characterized by short stature and multiple facial, limb and genital abnormalities. Additionally, some types of cognitive disorders may occasionally be present. Up to now, the FGD1 gene on the X chromosome is the only gene known to be associated with Aarskog syndrome.
Causes of Aarskog Syndrome
A mutation of the FGD1 gene, otherwise known as the faciogenital dysplasia 1 gene, is the cause of this syndrome. This gene is located in the arm structure (at Xp11.21 position) of the X-chromosome and thus it is considered an X-linked inherited disorder.
Mode of Genetic Exhibition
Normally, of the 23 pairs of chromosomes that a human possesses, the last pair is anasomal, meaning that this chromosome determines the sex of a child. Male offspring have one X and one Y chromosome, while for a female there are two X chromosomes.
This particular disorder is X-linked recessive. Hence, in a male who has only one X-chromosome, if a mutation happens, this will likely result in the development of the disease.
In females who have two X chromosomes, if one allele is mutated, it does not show any major effects as the allele on the other X-chromosome compensates and they become carriers of the syndrome. Such people never exhibit any signs of the disease.