男子不妊症における常染色体転座

Abstract

1979年9月より5年間に, 不妊を主訴に大阪赤十字病院泌尿器科を受診した無精子症27人, 乏精子症45人に対し, 染色体検査を行った.1)無精子症に, 47, XXYを5例, 46, XY, 15p+, 46, XY, t(3;20;21), 46, XY, t(1;19)lqh+各1例を認めた.2)乏精子症に, 46, XdelY(q12), 46, XY, 14s+, 46, XY, t(14;21), 46, XY, t(3;16)各1例を認めた.46, XY, t(14;21)を精子数1×106/ml以下の高度乏精子症, 46, XY, t(3;16)は精子数27×106/mlであった.3)常染色体相互転座の4症例では, 46, XYt(3;16)で血清LHの軽度上昇を認める以外, 血清gonadotropin値, testosterone値に異常を認めなかった.4)常染色体転座のうち, 無精子症, 高度乏精子症の3症例に睾丸生検を施行したところ, すべて精母細胞でのspermatogenic arrestを示した.減数分裂染色体の検討でも, metaphase 1とmetaphase 2の間でarrestが生じていると判断された

Four balanced autosomal reciprocal translocations were found through mitotic chromosome analysis among 72 subfertile males, 27 with azoospermia and 45 with sperm counts below 40 X 10(6)/ml. They were 46, XY, t(3; 20; 21) with azoospermia, 46, XY, t(14; 21) with sperm counts below 1 X 10(6)/ml, 46, XY, t(1; 19) lqh+ with azoospermia and 46, XY, t(3; 16) with sperm counts 27 X 10(6)/ml. Histological, cytogenetic and hormonal analysis were performed. Testicular biopsies from the first 3 carriers revealed complete spermatogenic arrest at the spermatocyte stage and meiotic studies of the same biopsies showed severe reduction in numbers of cells in 2nd meiotic division. In spite of severely defective spermatogenesis, serum gonadotropins of the carriers were within normal range, except for LH of the 4th case. Other chromosomal aberrations observed were 5 Klinefelter's syndrome, 2 autosomal minor variants (46, XY, 15p+ and 46, XY, 14s+) and 1 small Y.