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Androgen insensitivity syndrome (AIS; OMIM 300068) is an X-linked recessive disorder characterized by evidence of feminization of the external genitalia at birth, abnormal secondary sexual development in puberty, and infertility in individuals with a 46,XY karyotype. AIS is caused by loss-of-function mutations in the gene encoding the androgen receptor (AR; OMIM 313700), and represents a spectrum of defects in androgen action and can be subdivided into three broad phenotypes: complete androgen insensitivity syndrome (CAIS), with typical female genitalia; partial androgen insensitivity syndrome (PAIS) with predominantly female, predominantly male, or ambiguous genitalia; and mild androgen insensitivity syndrome (MAIS) with unambiguous male genitalia. PAIS includes a diagnosis of Reifenstein syndrome (OMIM 312300). The incidence of AIS is 1/20,000-1/64,000 male births, and patients usually initially present with inguinal hernia (prepubertal) or primary amenorrhea (post pubertal). The basic defect is end-organ partial to complete unresponsiveness to androgen, the variation depending on the specific molecular defect. Reasons For Referral:
Testing Methodology:PCR amplification of the exons contained in the AR gene coding region will be performed on patient genomic DNA. Direct sequencing of amplification products is performed in both the forward and reverse directions using automated fluorescence dideoxy sequencing methods. Specimen Requirements:Blood: EDTA (purple-top) tubes: Adults: 14 cc; Child: 6 cc; Infant: 2-3 cc Turnaround Time:4 weeks CPT Codes and Prices:Index: 83891, 83898x16, 83894, 83904x32, 83909x32, 83912 Shipping
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