[Genetic analysis and reproductive intervention of 7 families with gonadal mosaicism for Duchenne muscular dystrophy].

OBJECTIVE: To explore the genetic basis for 7 families with gonadal mosaicism for Duchenne muscular dystrophy (DMD). METHODS: For the 7 families presented at the CITIC Xiangya Reproductive and Genetic Hospital from September 2014 to March 2022, clinical data were collected. Preimplantation genetic testing for monogenic disorders (PGT-M) was carried out for the mother of the proband from family 6. Peripheral venous blood samples of the probands, their mothers and other patients from the families, amniotic fluid samples from families 1 ~ 4 and biopsied cells of embryos cultured in vitro from family 6 were collected for the extraction of genomic DNA. Multiplex ligation-dependent probe amplification (MLPA) was carried out for the DMD gene, and short tandem repeat (STR)/single nucleotide polymorphism (SNP)-based haplotypes were constructed for the probands, other patients, fetuses and embryos. RESULTS: The results of MLPA showed that the probands and the fetuses/probands' brothers in families 1 ~ 4, 5, 7 had carried the same DMD gene variants, whilst the probands' mothers were all normal. The proband in family 6 carried the same DMD gene variant with only 1 embryo (9 in total) cultured in vitro, and the DMD gene of the proband's mother and the fetus obtained through the PGT-M were normal. STR-based haplotype analysis showed that the probands and the fetuses/probands' brothers in families 1 ~ 3 and 5 have inherited the same maternal X chromosome. SNP-based haplotype analysis showed that the proband from family 6 has inherited the same maternal X chromosome with only 1 embryo (9 in total) cultured in vitro. The fetuses in families 1 and 6 (via PGT-M) were both confirmed to be healthy by follow up, whilst the mothers from families 2 and 3 had chosen induced labor. CONCLUSION: Haplotype analysis based on STR/SNP is an effective method for judging gonad mosaicism. Gonad mosaicisms should be suspected for women who have given births to children with DMD gene variants but with a normal peripheral blood genotype. Prenatal diagnosis and reproductive intervention may be adapted to reduce the births of further affected children in such families.

Novel variants of the PCCB gene in Chinese patients with propionic acidemia.

BACKGROUND AND AIMS: Propionic acidemia (PA) is an autosomal recessive metabolic disorder caused by a deficiency of propionyl-CoA carboxylase and mutations in the PCCA and PCCB genes. In this study, we investigated the clinical characteristics of individuals with PA and conducted genetic analyses to provide new genetic evidence for the diagnosis of PA. MATERIALS AND METHODS: We conducted whole-exome sequencing and Sanger sequencing in four individuals with PA from three unrelated Chinese families. We also performed a structural analysis of the PCCB protein variants. Couples from the three families included in our study underwent in vitro fertilization with preimplantation genetic testing. RESULTS: We found five variants of PCCB. These biallelic variants were inherited from heterozygous parental carriers and were located in the functional domain, absent in human population genome datasets, and predicted to be deleterious. These findings indicate that the variants might be responsible for the clinical features observed in these particular patients with PA. Through successful embryo transfer and implantation, one of the couples fortunately gave birth to a healthy child. CONCLUSION: Overall, our study can expand the mutation spectrum of PCCB and provide useful information for the prenatal diagnosis of PA and genetic counseling for affected individuals.

Inhibition effect of Zedoary turmeric oil on Listeria monocytogenes and Staphylococcus aureus growth and exotoxin proteins production.

PURPOSE: Zedoary turmeric oil (ZTO), the steam extract of Curcuma zedoaria Rosc was researched for its chemical composition, antibacterial activity, and mechanism for countering two major food-borne pathogenic species, Listeria monocytogenes and Staphylococcus aureus. METHODOLOGY: Gas chromatography-mass spectrometry (GC-MS) was used to analyse and characterize the chemical composition of ZTO. Its MICs for the two bacterial species and growth curves were measured. Western blot and real-time reverse-transcription (RT)-PCR assays were utilized to elaborate the mechanism of the antibacterial effect of ZTO by examining the expression levels of virulence-related extracellular proteins. ELISA was used to explore the biological relevance. RESULTS: GC-MS revealed high contents of curzerene, eucalyptol, germacrone and (-)-g-elemene representing 28.45, 10.94, 10.77 and 10.54  %, respectively, of the whole components. The MICs of ZTO that combatted L. monocytogenes and S. aureus were similar (1-2 mg ml-1 ). After adding ZTO at increasing concentrations, there was an evident reduction in the transcription of hly, iap, hla, sea, seb and agrA in a dose-dependent manner. Furthermore, TNF-α accumulation in RAW264.7 cells stimulated by L. monocytogenes and S. aureus supernatants was restricted by a 1/4 MIC of ZTO. CONCLUSION: Overall, L. monocytogenes and S. aureus were comparably susceptible to ZTO. These data demonstrated that ZTO's antimicrobial property was mediated by the repression of the production of virulence factors involved in L. monocytogenes and S. aureus pathogenesis, a finding that can potentially further progress in the development of new anti-virulence drugs.

Blood lead levels and influencing factors among outpatient children from 2016 to 2018 in Zhuzhou / 中国学校卫生

Objective@#To investigate the blood lead level of outpatient children and associated factors in Zhuzhou, and to offer targeted advice for the prevention and control of lead exposure.@*Methods@#The lead level in blood of 1 600 children aged ≤14 years old and the content of serum calcium, iron, zinc, magnesium, copper were tested, and the children and their parents were given a questionnaire regarding influencing factors of blood lead exposure.@*Results@#The average blood lead level of the children was (95.2±46.5)μg/L, The proportion of children with blood lead level ≥100 μg/L was 25.7%. The blood lead level between boys and girls had a statistical differences(Z=1.85, 2.85, P<0.05). The blood lead level was negatively correlated with serum calcium, iron, zinc, magnesium and copper(F=16.80，P<0.01). The risk factors for lead exposure included frequently drinking canned or bottled soft drinks, failing to wash one’s hands before meals, taking popcorn frequently, using coal for heat and for cooking, and constantly sucking fingers or biting fingernails (OR=2.12, 1.57, 1.46, 1.78, 3.24, P<0.01).@*Conclusion@#The blood lead levels of children in Zhuzhou is higher than national average level. We should strengthen environmental protection and behavioral interventions, and regularly monitor lead exposure among children.

Reciprocal Translocation Carrier Diagnosis in Preimplantation Human Embryos.

Preimplantation genetic diagnosis (PGD) is widely applied in reciprocal translocation carriers to increase the chance for a successful live birth. However, reciprocal translocation carrier embryos were seldom discriminated from the normal ones mainly due to the technique restriction. Here we established a clinical applicable approach to identify precise breakpoint of reciprocal translocation and to further distinguish normal embryos in PGD. In the preclinical phase, rearrangement breakpoints and adjacent single nucleotide polymorphisms (SNPs) were characterized by next-generation sequencing following microdissecting junction region (MicroSeq) from 8 reciprocal translocation carriers. Junction-spanning PCR and sequencing further discovered precise breakpoints. The precise breakpoints were identified in 7/8 patients and we revealed that translocations in 6 patients caused 9 gene disruptions. In the clinical phase of embryo analysis, informative SNPs were chosen for linkage analyses combined with PCR analysis of the breakpoints to identify the carrier embryos. From 15 blastocysts diagnosed to be chromosomal balanced, 13 blastocysts were identified to be carriers and 2 to be normal. Late prenatal diagnoses for five carriers and one normal fetus confirmed the carrier diagnosis results. Our results suggest that MicroSeq can accurately evaluate the genetic risk of translocation carriers and carrier screen is possible in later PGD treatment.