{Reference Type}: Journal Article {Title}: A Novel Splicing Mutation c.335-1 G > A in the Cardiac Transcription Factor NKX2-5 Leads to Familial Atrial Septal Defect Through miR-19 and PYK2. {Author}: Jia L;Limeng D;Xiaoyin T;Junwen W;Xintong Z;Gang X;Yun B;Hong G; {Journal}: Stem Cell Rev Rep {Volume}: 0 {Issue}: 0 {Year}: Jul 2022 2 {Factor}: 6.692 {DOI}: 10.1007/s12015-022-10400-5 {Abstract}: Mutations of NKX2-5 largely contribute to congenital heart diseases (CHDs), especially atrial septal defect (ASD). We identified a novel heterozygous splicing mutation c.335-1G > A in NKX2-5 gene in an ASD family via whole exome sequencing (WES) and linkage analysis. Utilizing the human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes (hiPSC-CMs) as a disease model, we showed that haploinsufficiency of NKX2-5 contributed to aberrant orchestration of apoptosis and proliferation in ASD patient-derived hiPSC-CMs. RNA-seq profiling and dual-luciferase reporter assay revealed that NKX2-5 acts upstream of PYK2 via miR-19a and miR-19b (miR-19a/b) to regulate cardiomyocyte apoptosis. Meanwhile, miR-19a/b are also downstream mediators of NKX2-5 during cardiomyocyte proliferation. The novel splicing mutation c.335-1G > A in NKX2-5 and its potential pathogenic roles in ASD were demonstrated. Our work provides clues not only for deep understanding of NKX2-5 in cardia development, but also for better knowledge in the molecular mechanisms of CHDs.