Mutations of SYCP3 are rare in infertile Spanish men with meiotic arrest.

No functional SYCP3 exonic SNP was found in infertile Spanish patients with meiosis arrest, suggesting that SYCP3 mutations very likely are not relevant in Spain in genetic susceptibility to meiosis arrest, just as in other studied European populations.

Single nucleotide polymorphisms in succinate dehydrogenase subunits and citrate synthase genes: association results for impaired spermatogenesis.

Evaluation of the possible implication of the SDHA, SDHB, SDHC, SDHD and CS genes in non-obstructive male infertility was performed on the basis that sperm concentration in the ejaculate has been previously correlated with nuclear-encoded mitochondrial enzyme activities (the four subunits of succinate dehydrogenase/complex II of the respiratory chain and citrate synthase). We performed an exhaustive analysis of the five genes for the presence of sequence variants that could be associated with impairment of sperm production. blastn searches in the genomic sequence NCBI database evidenced the presence of highly homologous sequences elsewhere on the genome that can interfere with polymerase chain reaction experiments.