The histologic picture of meiotic arrest is rather constant. Meiotic arrest is characterized by germ cells that enter meiosis and undergo the first chromosomal reduction from 4n to 2n but are then unable to proceed further. This results ... The histologic picture of meiotic arrest is rather constant. Meiotic arrest is characterized by germ cells that enter meiosis and undergo the first chromosomal reduction from 4n to 2n but are then unable to proceed further. This results in tubules containing spermatocytes as the latest developmental stage of germ cells. Meiotically arrested spermatocytes accumulate in the tubules, degenerate, and are easily distinguishable from normal spermatocytes by their partially condensed chromosomes. Although the cause of infertility in patients with meiotic arrest often remains unidentified, this histologic picture can be observed in patients with nonidiopathic infertility as well, such as in the case of microdeletions of the Y chromosome, chromosomal abnormalities, and cryptorchidism, suggesting that different causal factors can result in the same effect (summary by Luetjens et al., 2004). - Phenotypic and Genetic Heterogeneity of Spermatogenic Failure SPGF1 represents an autosomal recessive form of spermatogenic failure associated with defects in meiosis. SPGF2 (108420) represents a form of spermatogenic failure associated with rearrangements on chromosome 1. Another form of spermatogenic failure (SPGF3; 606766), associated with asthenozoospermia, is caused by mutation in the SLC26A8 gene (608480) on chromosome 6p21. A form of azoospermia due to perturbations of meiosis (SPGF4; 270960) is caused by mutation in the SYCP3 gene (604759) on chromosome 12q23. Male infertility due to large-headed, multiflagellar, polyploid sperm (SPGF5; 243060) is caused by mutation in the AURKC gene (603495) on chromosome 19q13.43. Acrosome malformation resulting in globozoospermia (SPGF6; 102530) can be caused by mutation in the SPATA16 gene (609856) on chromosome 3q26.3. Spermatogenic failure-7 (SPGF7; 612997) is caused by mutation in the CATSPER gene (606389) on chromosome 11q13.1. Spermatogenic failure-8 (SPGF8; 613957) is caused by mutation in the NR5A1 gene (184757) on chromosome 9q33. Another form of globozoospermia (SPGF9; 613958) is caused by mutation in the DPY19L2 gene (613893) on chromosome 12q14.2. A form of spermatogenic failure with defective sperm annulus (SPGF10; 614822) is caused by mutation in the SEPT12 gene (611562) on chromosome 16p13. Spermatogenic failure-11 (SPGF11; 6115081) is caused by mutation in the KLHL10 gene (608778) on chromosome 17p21. Spermatogenic failure-12 (SPGF12; 615413) is caused by mutation in the NANOS1 gene (608226) on chromosome 10q26. For a discussion of X chromosome-linked spermatogenic failure, see 305700. For a discussion of Y chromosome-linked spermatogenic failure, see 400042. Azoospermia may be associated with variation in the HSF2 gene (see 140581.0001). Spermatogenic failure can also result from underlying endocrinologic disorders (see, e.g., hypogonadotropic hypogonadism, 146110) or ciliary dyskinesias (see, e.g., CILD1, 244400).
Eight cases of infertility are known (Ferguson-Smith, 1973) in which a deficiency in synapsis during meiosis is evident by a deficiency of chiasmas in meiotic preparations from the testes. Since 3 of the males had first-cousin parents, the ... Eight cases of infertility are known (Ferguson-Smith, 1973) in which a deficiency in synapsis during meiosis is evident by a deficiency of chiasmas in meiotic preparations from the testes. Since 3 of the males had first-cousin parents, the disorder is very likely to be autosomal recessive. Defective DNA repair was reported in the patient of Pearson et al. (1970), but Page (1973) could not demonstrate a defect in the patients she studied. The occurrence of a childless sister is also consistent with autosomal recessive inheritance (Baker et al., 1976; Hulten et al., 1974). Chaganti et al. (1980) described an inbred kindred with 2 affected sibs and reviewed the literature comprehensively.