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Aarskog Syndrome

Aarskog syndrome (AAS) is a rare genetic condition characterized by short stature and multiple facial, limb and genital abnormalities. Cognitive disorders including ADHD have also been seen in some patients with AAS.

At present, the FGD1 gene on the X chromosome is the only gene known to be associated with AAS, and thus it is an X-linked disorder. However, some familial cases of a similar syndrome have been reported without identifiable mutations in the FGD1 gene, and with familial inheritance patterns that resemble autosomal transmission1. As a result, there is some speculation that AAS may have multiple genetic modes of inheritance, or that a distinct “Aarskog-like syndrome” may exist. As access to thorough genetic testing expands, this may be clarified in the coming years.

Females with AAS

Female carriers of AAS can be entirely asymptomatic (lacking any features of disease) or have mild disease features, including short stature, widely-spaced eyes (hypertelorism), dysplastic ears, widow’s peak hairline, and short fingers (brachydactyly). One study in 2025 identified 7 AAS carrier mothers and found that some of these features were present in 5 of them, with the remaining 2 carriers completely unaffected2. Older studies have reported female carriers “frequently” showing varying and milder expression of the syndrome, however the specific prevalence has not been reported3. Across all reported cases to date, female signs and symptoms of AAS have been significantly milder than their affected male family members, without any cases of developmental delay or genital abnormalities in females2,4.

This page was last updated in July, 2026. Please note that research into females with this condition is limited and the number of reported cases is small. As a result, percentages and prevalence rates may not be accurate or widely applicable. Decisions regarding your own health should be made in consultation with your medical provider.

  1. Xu M, Qi M, Zhou H, et al. Familial syndrome resembling Aarskog syndrome. Am J Med Genet A. 2010;152A(8):2017-2022. doi:10.1002/ajmg.a.33487

  2. Turgut GT, Altunoglu U, Avcı Ş, et al. Aarskog Syndrome: Deep Phenotyping and Genomic Landscape of a New Cohort Including Adult Patients. Clin Genet. 2025;108(3):334-346. doi:10.1111/cge.14744
  3. Hoo JJ. The Aarskog (facio-digito-genital) Syndrome. Clin Genet. 1979;16(4):269-276. doi:10.1111/j.1399-0004.1979.tb00999.x
  4. Zanetti Drumond V, Sousa Salgado L, Sousa Salgado C, et al. The Prevalence of Clinical Features in Patients with Aarskog-Scott Syndrome and Assessment of Genotype-Phenotype Correlation: A Systematic Review. Genet Res. 2021;2021:6652957. doi:10.1155/2021/6652957