Azoospermia related to a unique karyotype: 45,XY,-13,-19,+der(19)t(13;19)(q12;p13)

摘要

Azoospermia, defined as the absence of spermatozoa in the ejaculate, affects approximately 10 to 20% of infertile men (Ezeh and Moore 2001; Brisset et al. 2005). And azoospermia is often related to chromosomal abnormalities, which are present in approximately 5% of infertile men and in 15% of azoospermic men (O’Flynn O’Brien et al. 2010). The most common chromosomal abnormality in azoospermic patients is 47,XXY (Wang et al. 2010). Commonly, chromosomal translocations occur as a chromosomal rearrangement in infertile men. Balanced reciprocal translocations, giving a 46-chromosome karyotype, and Robertsonian translocations, leading to a 45- chromosome karyotype, are observed in azoospermic males with the rates of 0.9% and 0.09%, respectively (Van Assche et al. 1996). Normally, balanced reciprocal and Robertsonian translocations do not affect the phenotype of the patients; however, the patients can produce a notable percentage of chromosomally unbalanced gametes (ranging from ~5 to >80%), which may show variable sperm counts, ranging from normal to azoospermia (Oliver-Bonet et al. 2005; Perrin et al. 2007).