PBL teaching design of medical genetics with the case of brachydactyly type A2.

Medical genetics, which is a frontier subject in biomedicine, is the clinical core of gene diagnosis and gene therapy. In the training of medical students, medical genetics plays an important role in bridging basic medicine and clinical medicine. In recent years, problem-based learning (PBL) has been widely used in medical education as an important method to cultivate the autonomous learning ability of medical students. In the current study, we designed and shared the research on brachydactyly type A2 (BDA2) as the main case of PBL teaching, in order to guide the students towards autonomous learning, and to cultivate independent analysis and problem solving ability instead of simple knowledge acquisition. Such excellent academic teaching will provide more high quality medical talents and internationally competitiveness for constructing a healthy China.

Identifying susceptibility genes for essential hypertension by transcriptome-wide association study.

Hypertension is a leading risk factor of cardiovascular disease and mortality in the population worldwide. Recently, hundreds of genomic loci were reported for hypertension by GWAS, however, the most SNPs are located in intergenic regions of genome, where a functional cause is difficult to determine. In the current study, a TWAS of hypertension was conducted using 452,264 individuals including 84,640 patients. KEGG and GO enrichment analyses were performed for the hypertension-related genes identified via TWAS. PPI network analysis based on the STRING database was also performed to detect TWAS-identified genes in hypertension. We have identified 18,420 genes from the GWAS summary data, and of those 1010 non-overlapping genes expression were significantly associated with hypertension after FDR correction (PFDR <0.05) in four tissues (left heart ventricle, aorta, whole blood, and peripheral blood). The KEGG and GO terms were mostly related to autoimmune mechanisms, and the autoimmune-related pathways have also been enriched using GO analysis for PPI genes. We further performed Mendelian randomization analysis, and the results supported a significant association between autoimmunity and hypertension. Moreover, 15 novel hypertension-susceptible genes were identified in all tissues, and five of the genes (RBM6, HLA-DRB5, UHRF1BP1, LYZ, and TMEM116) were associated with autoimmune system, which provide further evidence supporting an autoimmune mechanism in hypertension. In summary, our study supports that an autoimmune mechanism plays an important role in the development of hypertension, and these findings will provide new biological insights that will assist in deciphering the molecular etiology of hypertension.

Functional analysis of the long-range regulatory element of BMP2 gene.

Recently, several pedigree-based studies have shown that abnormal replication of an enhancer element regulatory region in the downstream of the bone morphogenetic protein 2 (BMP2) gene is the cause of brachydactyly type A2 (BDA2). However, the exact molecular function of this regulatory region is unclear, and even conflicting results have emerged. In this study, based on bioinformatics analysis, we amplified target fragments of different lengths in this regulatory region by PCR technology, including a highly conserved 2.1 kb core sequence and 3 fragments that can completely cover the core 2.1 kb fragment. Then, the gene recombination vectors were constructed, and the biological function of these fragments was analyzed by the dual-luciferase reporter gene technology system. We found that the highly conserved 2.1 kb fragment did not have enhancer activity, while all of three truncated fragments showed strong enhancer activity. The results suggest that the expression regulation mode of the BMP2 gene is very complex. For the downstream regulatory region, selecting fragments of different lengths may have different effects on the regulation of BMP2 expression, which may due to the fragments with different lengths carrying different regulatory elements in the number of types. In summary, this study revealed the complexity of BMP2 gene regulatory elements, and provided new clues and directions for the subsequent in-depth exploration of the molecular pathogenic mechanism of BDA2.