congenital anomalies, chromosome abnormalities, birth prevalence, newborns, Down syndrome Congenital anomalies are a worldwide health problem that places a burden on the family and society. Chromosome abnormalities are one of the leading causes for congenital anomalies in newborns. Despite the remarkable development in cytogenetic services in the past years, still there are limited data from Middle East countries. The current study aimed to evaluate the prevalence and patterns of chromosomal aberrations in newborns admitted to the neonatal intensive care unit (NICU) with major congenital anomalies at Medina province in the western region of Saudi Arabia. Out of 2,541 live births, 150 newborns were selected based on the presence of major birth defects. Demographic and clinical data were collected from hospital medical records and statistically analyzed. The prevalence of major congenital anomalies was 10.7/1,000 live births (95% CI: 9.076-12.583). The most common congenital anomalies in descending order were congenital heart disease, musculoskeletal and chromosome abnormalities. The birth prevalence of chromosome abnormalities was 4.22/1,000 live births (95% CI: 3.211-5.441). The most common chromosome abnormality was Down syndrome-nondisjunction type (66%). Advanced parental age was strongly associated with chromosome aberrations (p < 0.001) while consanguinity was evident in cases with normal karyotype (p < 0.001). High birth prevalence of chromosome abnormalities in newborns with congenital anomalies in Al Madinah was evident and advanced parental age is a potential risk factor. A local registry system for congenital anomalies is highly recommended to provide proper health services to high risk families.

Protein disulfide isomerase A6 (PDIA6) is an unfolded protein response (UPR)‐regulating protein. PDIA6 regulates the UPR sensing proteins, Inositol requiring enzyme 1, and EIF2AK3. Biallelic inactivation of the two genes in mice and humans resulted in embryonic lethality, diabetes, skeletal defects, and renal insufficiency. We recently showed that PDIA6 inactivation in mice caused embryonic and early lethality, diabetes and immunodeficiency. Here, we present a case with asphyxiating thoracic dystrophy (ATD) syndrome and infantile‐onset diabetes. Whole exome sequencing revealed a homozygous frameshift variant in the PDIA6 gene. RNA expression was reduced in a gene dosage‐dependent manner, supporting a loss‐of‐function effect of this variant. Phenotypic correlation with the mouse model recapitulated the growth defect and delay, early lethality, coagulation, diabetes, immunological, and polycystic kidney disease phenotypes. In general, the phenotype of the current patient is consistent with phenotypes associated with the disruption of PDIA6 and the sensors of UPR in mice and humans. This is the first study to associate ATD to the UPR gene, PDIA6. We recommend screening ATD cases with or without insulin‐dependent diabetes for variants in PDIA6.