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Undermasculinized genitalia in a boy with an abnormally expanded CAG repeat length in the androgen receptor gene ★
Author(s) -
Ogata Tsutomu,
Muroya Koji,
Ishii Tomohiro,
Suzuki Yasuhiro,
Nakada Teruhiro,
Sasagawa Isoji
Publication year - 2001
Publication title -
clinical endocrinology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.055
H-Index - 147
eISSN - 1365-2265
pISSN - 0300-0664
DOI - 10.1046/j.1365-2265.2001.01205.x
Subject(s) - endocrinology , medicine , androgen receptor , dihydrotestosterone , exon , testosterone (patch) , hypospadias , androgen , biology , human chorionic gonadotropin , gonadotropin , hormone , gene , anatomy , genetics , prostate cancer , cancer
We report an 11‐year‐old boy with undermasculinized genitalia and an abnormally expanded CAG repeat length at exon 1 of the androgen receptor (AR) gene. He had microphallus and scrotal hypospadias with chordee, and underwent urethroplasty at 4 years of age. At 11 years of age, a gonadotropin releasing hormone (GnRH) test yielded a relatively high leutinizing hormone (LH) response (0·7→20·4 IU/l) and a relatively low follicle‐stimulating hormone (FSH) response (1·7→4·8 IU/l), and an human chorionic gonadotropin (hCG) test showed sufficient responses of testosterone (0·7→23·0 nmol/l) and dihydrotestosterone (0·38→2·95 nmol/l). The CAG repeat length was 44 for the boy and ranged from 12 to 32 for 100 control males. The DNA sequences of the AR gene were normal for the exons 1–8 and for the splice donor, splice acceptor and branch sites. The markedly expanded CAG repeat length appears to be relevant to the undermasculinized genitalia of this boy, because such an expandsion, which has previously been reported only in spinal and bulbar muscular atrophy, is known to reduce AR function.