Aarskog–Scott syndrome | |
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Classification and external resources | |
Specialty | medical genetics |
ICD-10 | Q87.1 |
ICD-9-CM | 759.89 |
OMIM | 100050 |
DiseasesDB | 29329 |
MedlinePlus | 001654 |
MeSH | C535331 |
Orphanet | 915 |
Aarskog–Scott syndrome is a rare disease inherited as autosomal dominant or X-linked and characterized by short stature, facial abnormalities, skeletal and genital anomalies.
The Aarskog–Scott syndrome (AAS) is also known as the Aarskog syndrome, faciodigitogenital syndrome, shawl scrotum syndrome and faciogenital dysplasia.
The Aarskog–Scott syndrome is a disorder with short stature, hypertelorism, downslanting palpebral fissures, anteverted nostrils, joint laxity, shawl scrotum, and developmental delays. The physical phenotype varies with age and postpuberal males may have only minor remnant manifestations of the prepuberal phenotype.
Aarskog–Scott syndrome is transmitted in an X-linked recessive manner. The sons of female carriers are at 50% risk of being affected with the syndrome. The daughters of female carriers are at 50% risk of being carriers themselves. Females may have mild manifestations of the syndrome. The syndrome is caused by mutation in a gene called FGD1 in band p11.21 on the X chromosome.
The Aarskog–Scott syndrome is due to mutation in the FGD1 gene. FGD1 encodes a guanine nucleotide exchange factor (GEF) that specifically activates Cdc42, a member of the Rho (Ras homology) family of the p21 GTPases. By activating Cdc42, FGD1 protein stimulates fibroblasts to form filopodia, cytoskeletal elements involved in cellular signaling, adhesion, and migration. Through Cdc42, FGD1 protein also activates the c-Jun N-terminal kinase (JNK) signaling cascade, a pathway that regulates cell growth, apoptosis, and cellular differentiation.