임상연구 : 한국인 안드로젠 저항성 증후군 환자의 안드로젠 수용체 유전자 변이 양상

Androgen insensitivity syndrome (AIS) is a X-linked disorder of sexual differentiation resulting from defective androgen receptor (AR) function. Androgens are secreted by the testes of 46,XY individuals, but there is loss of target organ response to the hormone. The abnormalities of AR are due to defects in the AR gene, and many mutations causing AIS have been reported since the cloning of AR gene. In this study, we analyzed the AR genes in twelve Korean patients with androgen insensitivity syndrome: 9 patients with complete AIS and 3 patients with partial AIS. DNAs were isolated from patients with AIS, and the coding region of AR gene was amplified by a polymerase chain reaction using 7 pairs of primers (exon B-H). Sequence analysis of the AR gene was performed using direct sequencing and single strand conformational polymorphism (SSCP). The AR gene mutations were identified in 7 out of 12 patients: 6 of 9 patients with complete AIS, and one of 3 patients with partial AIS. Mutations found were as follows: the point mutation (ATT→ACT) at position 680 of exon D, point mutation (TGG→TGC) at position 751 of exon E, point mutation (CAA→TAA) at position 792 of exon F, point mutations (CGC→TGC, GTG→ATG) at position 855 and 866 of exon G, and the deletion of 13 nucleotides (CGTATCATTGCAT) at position 840 of exon G, respectively. To the best of our knowledge, the point mutations found in exon D, exon E, and exon F, and the deletion in exon G have not been observed before. SSCP revealed bands with abnormal mobility in 10 out of 12 patients tested. Mutations were found 5 out of these 10 patients. The other two patients showed no abnormal band on SSCP, but showed mutations by direct sequencing. In conclusion, we have demonstrated the AR gene mutations, including three novel mutations, in Korean patients with AIS, and these abnormalities might be related to the pathogenesis of androgen insensitivity syndrome.