Objective To investigate germline mutation of breast cancer susceptibility genes BRCA1/2,TP53 and PTEN in Chinese breast cancer patients. Methods All of128 female breast cancer patients in Peking University People′s Hospital from January 2016 to August 2018 were selected as objects. Among them,44 cases were sporadic breast cancer and 84 werebreast cancer patients with genetic high risks. Germline mutations of BRCA1,BRCA2,TP53 and PTENwere detected by NGS.χ2 test was used to analyze the difference of pathogenic mutation rates between sporadic breast cancer group and breast cancer with high genetic risks.Groups were divided according to the clinical features of the patients(family history, triple-negative breast cancer,age and bilateral breast cancer).Among them,there were 42 cases with family history of breast cancer,34 cases of triple-negative breast cancer,33 cases of early-onset breast cancer and 7 cases of bilateral breast cancer. Fisher′s exact probability test compared the relationship between pathogenic mutations of BRCA1/2 gene and clinical characteristics of breast cancer patients with hereditary risk factors. Results In 128 cases of breast cancer,30 germline mutations of BRCA1/2 were detected, including 13 pathogenic mutations and 3 newly discovered mutations(BRCA1:c. 4760C>G,BRCA2:c. 44134414del and BRCA2:c. 64826485del). The new mutations may be unique mutations of Chinese population. There were 3 cases of TP53 mutations,including 1 pathogenic mutation. All of the 3 mutations were found in early-onset breast cancer. Germline mutation of T53 has important detection significance for early-onset hereditary breast cancer. There were 5 cases of PTEN mutations,including 3 pathogenic mutations. Among 84 breast cancer patients with genetic high risks,the carry mutation rate was 40.5％(34/84)and the pathogenic mutation rate was 15.4(13/84). Among 44 sporadic cases,the carry mutation rate was 9％(4/44). The pathogenic mutation rate was 6.8％(3/44). Breast cancer susceptibility genes were carried at a higher rate in breast cancer patients with genetic high risks(P<0.001). BRCA1/2 mutations did not show statistical differences among groups of breast cancer patients with hereditary high risk factors . Conclusion Germline mutation detection of breast cancer susceptibility genes by next-generation sequencing is of great significance in breast cancer risk prediction and prognosis evaluation.

Objective To determine the distribution of common deafness gene mutations by microarray-PCR in pregnant women of Beijing, then explore their prevalence and clinical significance. Methods Totally 1709 pregnant women were prospectively enrolled from the outpatients of Obstetrical Clinical from Peking University Peoples' Hospital in this study from June 2016 to April 2018. Peripheral blood samples were obtained and DNA templates were extracted from all subjects. The coding region of the GJB2 gene(35del G, 235delC, 176-191del16, 299-300delAT), SLC26A4 gene(IVS7-2 A>G, 2168A>G), 12sRNA gene(1494C>T,1555A>G) and GJB3 gene(538 C>T)were detected by microarray-PCR. Meanwhile,256 cases firstly recruited in this study were confirmed by Sanger sequencing. The analysis was performed to explore the distribution of deafness gene mutations and the subjects detected to be positive were further followed up until they had given birth to their babies.Results Among 1709 pregnant women, 89 cases were found to be carrying at least one mutation sites(5.21％).Among them,83 cases were heterozygous mutation(35 cases of GJB2235delC, 12 cases of GJB2299-300delAT mutation, one case of GJB2176-191del 16, 30 cases of SLC26A4 IVS 7-2 A>G, 3 cases of SLC26A42168 A>G and two cases of GJB3538 C>T). There were one case of 235delC homozygous mutation and 2 cases of double mutations(IVS7-2 A>G /GJB2299-300delAT, IVS7-2 A>G/GJB2235delC). The positive rate of 235delC, 299-300delAT and 176-191del16 was 2.17％, 0.76％and 0.06％, respectively. As to SLC26A4, 1.87％of the pregnant women were carrying IVS 7-2 A>G and 0.18％for 2168 A>G. Two cases were detected carrying GJB3 C>T mutation and three for 12s RNA1555 A>G mutation, respectively. The results of microarray-PCR were identical to those of Sanger sequencing, with the coincidence of 100％.26 spouses of the 56 cases were followed up. Two proved to be carrier of the same gene mutation. One of their babies was born with normal hearing until the end of this research, while another baby was born deafness and implant cochlear when three month old. Conclusions GJB2235delC and SLC26A4 IVS 7-2 A>G were the most prevalent mutations in pregnant women of Beijing, and it may provide guidance to eugenics and early clinical intervention.

Objective The single nucleotide polymorphisms (SNPs) of APOE and SLCO1B1 were examined to explore their association with the risk and severity of coronary heart disease(CAD). Methods A total of 1267 cases of consecutive coronary heart disease (CAD)-suspected inpatients visiting department of Cardiology in Peking University Peoples' Hospital from March 2017 to november were recruited into this case-control study, and then 391 CAD cases and 223 non-CAD controls were enrolled for final analysis after screening by coronary angiography and exclusion criteria. The severity of the CAD cases were evaluated according to Gensini scores. The SNPs of APOE(388T>C, 526C>T) and SLCO1B1(388A>G, 521T>C) were detected using Real-time PCR and further verified using Sanger sequencing. Environmental risk factors were collected, and the correlations between SNPs of APOE and SLCO1B1 and the risk and severity of CAD were performed by SPSS version 16.0. Results The SNPs of all the subjects included in CAD group and non-CAD group were successfully detected, with an accordance of 100％ to Sanger sequencing. The distribution of APOE and SLCO1B1 gene were subjected to Hardy-Weinberg. The distributions of APOE gene ε3/ε3 genotypes and ε3 allele were most commonly found in both CAD group and non-CAD group (ε3/ε3: 70.8％,73.1％;ε3: 83.5％,85.2％;respectively). APOE genotypes and alleles were comparable between the CAD cases and non-CAD controls (P>0.05). The frequencies of APOE gene ε4+genotype were more likely to be found in the subgroup of CAD with Gensini score≥72 (P<0.05). The distributions of SLCO1B1 gene *1b/*1b genotypes and *1b allele were most commonly found in both CAD group and non-CAD group (*1b/*1b: 37.3％, 36.8％; *1b: 60.1％, 61.7％; respectively). There was no significant difference in genotype and allele frequencies of SLCO1B1 between the two groups and among subgroups with different severity of CAD (P>0.05). Conclusion This study observed no association between SNPs of APOE, SLCO1B1 and the risk of CAD in this population. However, APOE gene ε4 +genotype may increase the severity of CAD.