Identification of 1q21.1 microduplication in a family: A case report

BACKGROUND

Copy number variation (CNV) has become widely recognized in recent years due to the extensive use of gene screening in developmental disorders and epilepsy research. 1q21.1 microduplication syndrome is a rare CNV disease that can manifest as multiple congenital developmental disorders, autism spectrum disorders, congenital malformations, and congenital heart defects with genetic heterogeneity.

CASE SUMMARY

We reported a pediatric patient with 1q21.1 microduplication syndrome, and carried out a literature review to determine the correlation between 1q21.1 microduplication and its phenotypes. We summarized the patient’s medical history and clinical symptoms, and extracted genomic DNA from the patient, her parents, elder brother, and sister. The patient was an 8-mo-old girl who was hospitalized for recurrent convulsions over a 2-mo period. Whole exon sequencing and whole genome low-depth sequencing (CNV-seq) were then performed. Whole exon sequencing detected a 1.58-Mb duplication in the CHR1:145883867-147465312 region, which was located in the 1q21.1 region. Family analysis showed that the pathogenetic duplication fragment, which was also detected in her elder brother’s DNA originated from the mother.

CONCLUSION

Whole exon sequencing combined with quantitative polymerase chain reaction can provide an accurate molecular diagnosis in children with 1q21.1 microduplication syndrome, which is of great significance for genetic counseling and early intervention.

Cooking oil fume-induced cytokine expression and oxidative stress in human lung epithelial cells

Epidemiological studies have shown an association between exposure to indoor air pollution from Chinese-style cooking and risk of lung cancer among Chinese females. Several toxic substances have been identified in cooking oil fumes (COF) collected from heated rapeseed oil. In this study, we examined the biological effects of COF on CL3 human lung epithelial cells. Exposure to 200 microg/ml COF significantly reduced cell growth within 4 days. In addition, we examined the effect of COF on TGFbeta1, TGFbeta2, IL-6, IL-8, and IFN-gamma gene expressions with the RT-PCR method. We found that TGFbeta1 mRNA levels increased after exposure to 200 microg/ml COF for 24 h. Similarly, exposure to 10 microM benzo[a]pyrene or 100 nM 12-O-tetradecanoylphorbol-13-acetate increased TGFbeta1 mRNA levels at 24 h. The mRNA levels of TGFbeta2, IL-6, IL-8, and IFN-gamma did not increase after treatment with COF, benzo[a]pyrene, or 12-O-tetradecanoylphorbol-13-acetate. COF-induced TGFbeta1 production was confirmed by quantification of TGFbeta1 in conditioned medium with enzyme-linked immunosorbent assay. Exposure to 200 microg/ml COF significantly increased TGFbeta1 secretion in a time-dependent and dose-dependent manner. It has been demonstrated that reactive oxygen intermediates induce TGFbeta1 gene expression. When CL3 cells were exposed to 200 microg/ml COF for 15 min, there was an increase in intracellular peroxide formation with the dichlorofluorescein method. Furthermore, treatment with 200 microg/ml COF for 12 h also significantly induced lipid peroxidation in CL3 cells. Our results show that exposure to COF inhibits cell growth, increases TGFbeta1 secretion, and induces oxidative stress in CL3 lung epithelial cells. This suggests that TGFbeta1 and oxidative stress play a role in the biological effects of COF on lung epithelial cells.

Genetic polymorphisms of NAD(P)H quinone oxidoreductase, CYP1A1 and microsomal epoxide hydrolase and lung cancer risk in Nanjing, China

Genetic variations in metabolic activation or detoxification enzymes have been thought to contribute to individual differences in lung cancer susceptibility. Genetic polymorphisms of NAD(P)H quinone oxidoreductase (NQO1), cytochrome P4501A1 (CYP1A1) and microsomal epoxide hydrolase (HYL1) have been associated with increased lung cancer risk in Asian populations. In the present study, the possibility of an association of NQO1, CYP1A1 and HYL1 genetic polymorphisms with lung cancer was examined among residents in Nanjing, China. A total of 84 lung cancer patients and 84 control subjects were matched by age, gender, occupation and smoking status. No significant association was observed for these genetic polymorphisms with the overall incidence of lung cancer. When the groups were stratified according to smoking status, we found that smokers carrying the HYL1*2 allele had a higher relative risk for lung cancer Odds ratio ((OR), 5.66; 95% confidence interval (95% CI), 1.71-18.68). The association was also found with squamous cell carcinoma (OR, 3.23; 95% CI, 1.00-10.38). Our results suggest that HYL1*2 polymorphism might be a risk factor for smoking-associated lung cancer in China.