Adriamycin induces H2AX phosphorylation in human spermatozoa

Aim： To investigate whether adriamycin induces DNA damage and the formation of γH2AX （the phosphorylated form of histone H2AX） foci in mature spermatozoa. Methods： Human spermatozoa were treated with adriamycin at different concentrations, γH2AX was analyzed by immunofluorescent staining and flow cytometry and doublestrand breaks （DSB） were detected by the comet assay. Results： The neutral comet assay revealed that the treatment with adriamycin at 2 μg/mL for different times （0.5, 2, 8 and 24 h）, or for 8 h at different concentrations （0,4, 2 and 10 μg/mL）, induced significant DSB in spermatozoa. Immunofluorent staining and flow cytometry showed that the expression of γH2AX was increased in a dose-dependent and time-dependant manner after the treatment of adriamycin. Adriamycin also induced the concurrent appearance of DNA maintenance/repair proteins RAD50 and 53BP 1 with γH2AX in spermatozoa. Wortmannin, an inhibitor of the phosphatidylinositol 3-kinase （PI3K） family, abolished the co-appearance of these two proteins with γH2AX. Conclusion： Human mature spermatozoa have the same response to DSB-induced H2AX phosphorylation and subsequent recruitment of DNA maintenance/ repair proteins as somatic cells.

Comprehensive genetic diagnosis of patients with Duchenne/Becker muscular dystrophy(DMD/BMD) and pathogenicity analysis of splice site variants in the DMD gene

Duchenne muscular dystrophy(DMD)and Becker muscular dystrophy(BMD)are caused by mutations in the DMD gene.The aim of this study is to identify pathogenic DMD variants in probands and reduce the risk of recurrence of the disease in affected families.Variations in 100 unrelated DMD/BMD patients were detected by multiplex ligation-dependent probe amplification(MLPA)and next-generation sequencing(NGS).Pathogenic variants in DMD were successfully identified in all cases,and 11 of them were novel.The most common mutations were intragenic deletions(69%),with two hotspots located in the 5'end(exons 2–19)and the central of the DMD gene(exons 45–55),while point mutations were observed in 22%patients.Further,c.1149+1G>A and c.1150?2A>G were confirmed by hybrid minigene splicing assay(HMSA).This two splice site mutations would lead to two aberrant DMD isoforms which give rise to severely truncated protein.Therefore,the clinical use of MLPA,NGS,and HMSA is an effective strategy to identify variants.Importantly,eight embryos were terminated pregnancies according to prenatal diagnosis and a healthy boy was successfully delivered by preimplantation genetic diagnosis(PGD).Early and accurate genetic diagnosis is essential for prenatal diagnosis/PGD to reduce the risk of recurrence of DMD in affected families.

Effects of pre-pregnancy body mass index and gestational weight gain on neonatal birth weight

To evaluate the effects of maternal pre-pregnancy body mass index （pre-BMI） and gestational weight gain （GWG） on neonatal birth weight （NBW） in the population of Chinese healthy pregnant women, attempting to guide weight control in pregnancy. A retrospective cohort study of 3772 Chinese women was conducted. The population was stratified by maternal pre-BMI categories as underweight （〈18.5 kg/m2）, normal weight （18.5-23.9 kg/m2）, overweight （24.0-27.9 kg/m2）, and obesity （〉28.0 kg/m2）. The NBW differences were tested among the four groups, and then deeper associations among maternal pre-BMI, GWG, and NBW were investigated by multivariate analysis. NBW increased significantly with the increase of maternal pre-BMI level （P〈0.05）, except overweight to obesity （P〉0.05）. The multivariate analysis showed that both pre-BMI and GWG were positively correlated with NBW （P〈0.05）. Compared with normal pre-BMI, underweight predicted an increased odds ratio of small-for-gestational-age （SGA） and decreased odds ratio for macrosomia and large-for-gestational-age （LGA）, and the results were opposite for overweight. With the increase of GWG, the risk of SGA decreased and the risks of macrosomia and LGA increased. In addition, in different pre-BMI categories, the effects of weight gain in the first trimester on NBW were different （P〈0.05）. NBW is positively affected by both maternal pre-BMI and GWG, extreme pre-BMI and GWG are both associated with increased risks of abnormal birth weight, and maternal pre-BMI may modify the effect of weight gain in each trimester on NBW. A valid GWG guideline for Chinese women is an urgent requirement, whereas existing recommendations seem to be not very suitable for the Chinese.

The association between the two more common genetic causes of spermatogenic failure:a 7-year retrospective study

Chromosomal abnormalities and Y chromosome microdeletions are considered to be the two more common genetic causes of spermatogenic failure.However,the relati on ship between chromosomal aberrations and Y chromosome microdeletio ns is still un clear.This study was to investigate the incidenee and characteristics of chromosomal aberrations and Y chromosome microdeletions in infertile men,and to explore whether there was a correlation between the two genetic defects of spermatogenic failure.A 7-year retrospective study was conducted on 5465 infertile men with nonobstructive azoospermia or oligozoospermia.Karyotype analysis of peripheral blood lymphocytes was performed by standard G-banding techniques.Y chromosome microdeletions were screened by multiplex PCR amplification with six specific sequence-tagged site(STS)markers.Among the 5465 infertile men analyzed,371(6.8%)had Y chromosome microdeletions and the prevalence of microdeletions in azoospermia was 10.5%(259/2474)and in severe oligozoospermia was 6.3%(107/1705).A total of 4003(73.2%)infertile men underwent karyotyping;370(9.2%)had chromosomal abnormalities and 222(5.5%)had chromosomal polymorphisms.Karyotype analysis was performed on 272(73.3%)patients with Y chromosome microdeletions and 77(28.3%)had chromosomal aberrations,all of which involved sex chromosomes but not autosomes.There was a sign ifica nt d iff ere nee in the frequency of chromosomal abno rmalities betwee n men with and without Y chromosome microdeletions(P<0.05).