Androgen insensitivity syndrome (AIS) is the most common cause of 46,XY disorders of sex development (46,XY DSD). This syndrome is an X-linked inheritance disease and it is caused by mutations in the human androgen receptor (AR) gene. Non-synonymous point AR mutations are frequently described in this disease, including in the complete phenotype. We present a novel synonymous mutation in the human AR gene (c.1530C > T) in four 46,XY patients from two unrelated families associated with complete androgen insensitivity syndrome (CAIS). The analysis of mRNA from testis showed that synonymous AR mutation changed the natural exon 1 donor splice site, with deletion of the last 92 nucleotides of the AR exon 1 leading to a premature stop codon 12 positions ahead resulting in a truncate AR protein. Linkage analyses suggested a probable founder effect for this mutation. In conclusion, we described the first synonymous AR mutation associated with CAIS phenotype, reinforcing the disease-causing role of synonymous mutations.
Keywords: Androgen insensitivity syndrome; Androgen receptor; Complete androgen insensitivity; DSD 46,XY; Disorders of sexual development; Synonymous mutations.
Copyright © 2017 Elsevier Ltd. All rights reserved.