Congenital heart defects (CHDs), a wide variety of developmental abnormalities in the structures of the heart and the great thoracic blood vessels, are the most common form of birth defect in humans worldwide. CHDs are accountable for substantial morbidity and are still the leading cause of birth defect‑related deaths. Recent studies have demonstrated the pivotal roles of genetic defects in the pathogenesis of CHDs, and a great number of genetic mutations have been associated with CHDs. Nevertheless, CHDs are a genetically heterogeneous disorder and the genetic basis underlying CHDs in an overwhelming majority of cases remains unclear. In the present study, the coding exons and flanking introns of the heart and neural crest derivatives expressed transcript 1 (HAND1) gene, which encodes a basic helix‑loop‑helix transcription factor crucial for cardiovascular development, were sequenced in 158 unrelated patients with CHDs, and a de novo heterozygous mutation, p.K132X, was identified in a patient with double outlet right ventricle (DORV), as well as ventricular septal defect. The nonsense mutation, which was predicted to produce a truncated HAND1 protein lacking 84 carboxyl‑terminal amino acids, was absent in 600 control chromosomes. Functional analyses revealed that the HAND1 K132X mutant had no transcriptional activity. Furthermore, the mutation disrupted the synergistic activation between HAND1 and GATA binding protein 4 (GATA4), another cardiac core transcription factor causally linked to CHDs. To the best of our knowledge, this is the first report on the association of HAND1 loss‑of‑function mutation with an enhanced susceptibility to DORV in humans. These findings expand the phenotypic spectrum linked to HAND1 mutations, suggesting potential implications for the development of novelo prophylactic and therapeutic strategies for DORV.

Congenital heart disease (CHD) is the most common form of birth defect in humans, and remains a leading non‑infectious cause of infant mortality worldwide. An increasing number of studies have demonstrated that genetic defects serve a pivotal role in the pathogenesis of CHD, and mutations in >60 genes have been causally associated with CHD. CHD is a heterogeneous disease and the genetic basis of CHD in the majority of patients remains poorly understood. In the present study, the coding exons and flanking introns of the mesoderm posterior 1 (MESP1) gene, which encodes a basic helix‑loop‑helix transcription factor required for normal cardiovascular development, were sequenced in 178 unrelated patients with CHD. The available relatives of the index patient carrying an identified mutation and 200 unrelated, ethnically‑matched healthy individuals, who were used as controls, were genotyped for MESP1. The functional characteristics of the MESP1 mutation were determined using a dual‑luciferase reporter assay system. As a result, a novel de novo heterozygous MESP1 mutation, p.Q118X, was identified in an index patient with double outlet right ventricle (DORV) and a ventricular septal defect. The nonsense mutation was absent in the 400 reference chromosomes and the altered amino acid was completely conserved evolutionarily across species. Functional assays indicated that the mutant MESP1 protein had no transcriptional activity when compared with its wild‑type counterpart. The present study firstly provided experimental evidence supporting the concept that a MESP1 loss‑of‑function mutation may contribute to the development of DORV in humans, which presents a significant insight into the molecular pathogenesis of CHD. The results highlight the potential implications for the genetic counseling and personalized treatment of patients with CHD.

A system consisting of catalytic amounts of [Rh(CH 2 = CH 2 )Cl] 2 / PPh 2 Cy, and PhCl as the solvent efficiently catalyzes selective rearrangement of aldoximes to furnish various primary amides in moderate to good yields. Replacing the [Rh(CH 2 = CH 2 )Cl] 2 with Rh(NBD) 2 OTf enables the superior transformation to afford the amides with up to 99% yields. Attractive synthetic features associated with this methodology include absence of cocatalysts, broad functional group tolerance, good to excellent yields, low metal loadings, and operational convenience.[a] Dr.