Global methylation status of sperm DNA in carriers of chromosome structural aberrations

Male infertility might be clearly associated with aberrant DNA methylation patterns in human spermatozoa. An association between oxidative stress and the global methylation status of the sperm genome has also been suggested. The aim of the present study was to determine whether the global sperm DNA methylation status was affected in the spermatozoa of carriers of chromosome structural aberrations. The relationships between the 5-methylcytosine （msC） levels in spermatozoa and chromatin integrity status were evaluated. The study patients comprised male carriers of chromosome structural aberrations with reproductive failure （n = 24）, and the controls comprised normozoospermic sperm volunteers （n = 23）. The global msC level was measured using thin-layer chromatography （TLC） and immunofluorescence （IF） techniques. The sperm chromatin integrity was assessed using aniline blue （AB） staining and TUNEL assay. The mean msC levels were similar between the investigated chromosome structural aberrations carriers （P） and controls （K）. However, sperm chromatin integrity tests revealed significantly higher values in chromosomal rearrangement carriers than in controls （P 〈 0.05）. Although the potential relationship between sperm chromatin integrity status and sperm DNA fragmentation and the msC level juxtaposed in both analyzed groups （P vs K） was represented in a clearly opposite manner, the low chromatin integrity might be associated with the high hypomethylation status of the sperm DNA observed in carriers of chromosome structural aberrations.

Comprehensive semen examination in patients with pancreatic-sufficient and pancreatic-insufficient cystic fibrosis

We examined a cohort of 93 cystic fibrosis(CF)male patients who were pancreatic-sufficient(PS-CF;n=40)or pancreatic-insufficient(PI-CF;n=53).Complex semen examination was performed,including standard semen analysis,quantitative karyological analysis(QKA)of immature germ cells(IGCs),transmission electronic microscopy(TEM),biochemical analysis,and sperm DNA fragmentation by terminal deoxynucleotidyl transferase-mediated dUTP nickend labeling(TUNEL)assay.Azoospermia was diagnosed in 83(89.2%)patients.The other 10(10.8%)patients were found to be nonazoospermic and showed various spermatological diagnoses(asthenozoospermia,n=2;asthenoteratozoospermia,n=3;oligoasthenozoospermia,n=1;oligoasthenoteratozoospermia,n=3;and normozoospermia,n=1)with no specific morphological abnormalities.Oligospermia was detected in 89.2%azoospermic and 30.0%nonazoospermic patients.Low seminal pH(<7.0)was found in 74(89.2%)of 83 azoospermic patients.Moderate leukocytospermia(2.0×10^(6)-2.2×10^(6)ml^(-1))was revealed in 2.4%azoospermic and 40.0%nonazoospermic semen samples.The signs of partial meiotic arrest at prophase I were found in 4 of 6 nonazoospermic patients examined by QKA of IGCs.The content of fructose and citrate was low in oligospermic and normal in nonoligospermic semen samples.An increased percentage(>30%)of spermatozoa with noncondensed(“immature”)chromatin was revealed in 2 of 6 nonazoospermic semen samples analyzed by TEM.

Genes associated with testicular germ cell tumors and testicular dysgenesis in patients with testicular microlithiasis

Testicular microlithiasis （TM） is one of the symptoms of testicular dysgenesis syndrome （TDS）. TM is particularly interesting as an informative marker of testicular germ cell tumors （TGCTs）. KIT ligand gene （KITLG）, BCL2 antagonist/killer 1 （BAK1）, and sprouty RTK signaling antagonist 4 （SPRY4） genes are associated with a high risk of TGCTs, whereas bone morphogenetic protein 7 gene （BMP7）, transforming growth factor beta receptor 3 gene （TGFBR3）, and homeobox D cluster genes （HOXD） are related to TDS. Using polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP） analysis, we investigated allele and genotype frequencies for KITLG （rs995030, rs1508595）, SPRY4 （rs4624820, rs6897876）, BAK1 （rs210138）, BMP7 （rs388286）, TGFBR3 （rs12082710）, and HOXD （rs17198432） in 142 TGCT patients, 137 TM patients, and 153 fertile men （control group）. We found significant differences in the KITLG GG_rs995030 genotype in TM （P= 0.01） and TGCT patients （P = 0.0005） compared with the control. We also revealed strong associations between KITLGrs1508595 and TM （G allele, P = 0.003; GG genotype, P= 0.01） and between KITLG_rs1508595 and TGCTs （G allele, P-- 0.0001; GG genotype, P = 0.0007）. Moreover, there was a significant difference in BMP7_rs388286 between the TGCT group and the control （T allele, P = 0.00004; TT genotype, P = 0.00006） and between the TM group and the control （T allele, P= 0.04）. HOXDalso demonstrated a strong association with TGCTs （rs17198432 A allele, P = 0.0001; AA genotype, P = 0.001）. Furthermore, significant differences were found between the TGCT group and the control in the BAK1_rs210138 G allele （P= 0.03） and the GG genotype （P= 0.01）. KITLG and BMP7genes, associated with the development of TGCTs, may also be related to TM. In summary, the KITLG GG_rs995030, GG_rs1508595, BMP7 TT_rs388286, HOXD AA_rs17198432, and BAK1 GG_rs210138 genotypes were associated with a high risk of TGCT development.