Malformations of the brain are common and vary in severity, from negligible to potentially fatal. Their causes have not been fully elucidated. Here, we report pathogenic variants in the core protein-folding machinery TRiC/CCT in individuals with brain malformations, intellectual disability, and seizures. The chaperonin TRiC is an obligate hetero-oligomer, and we identify variants in seven of its eight subunits, all of which impair function or assembly through different mechanisms. Transcriptome and proteome analyses of patient-derived fibroblasts demonstrate the various consequences of TRiC impairment. The results reveal an unexpected and potentially widespread role for protein folding in the development of the central nervous system and define a disease spectrum of “TRiCopathies.”
Several patients with rare genetic disorders remain undiagnosed following comprehensive diagnostic testing using whole-exome sequencing (WES). In these patients, pathogenic genetic variants may reside in intronic or regulatory regions or they may emerge through mutational mechanisms not detected by WES. For this reason, we implemented whole-genome sequencing (WGS) in routine clinical diagnostics of patients with undiagnosed genetic disorders and report on the outcome in 30 patients. Criteria for consideration included (1) negative WES, (2) a high likelihood of a genetic cause for the disorders, (3) positive family history, (4) detection of large blocks of homozygosity or (5) detection of a single pathogenic variant in a gene associated with recessive conditions. We successfully discovered a causative genetic variant in 6 cases, a retrotranspositional event in the APC gene, non-coding variants in the intronic region of the OTC gene and the promotor region of the UFM1 gene, repeat expansion in the RFC1 gene and a single exon duplication in the CNGB3 gene. We also discovered one coding variant, an indel, which was missed by variant caller during WES data analysis. Our study demonstrates the impact of WGS in the group of patients with undiagnosed genetic diseases after WES in the clinical setting and the diversity of mutational mechanisms discovered, which would remain undetected using other methods.
Obesity is an increasing worldwide problem, and it is common in women with polycystic ovaries syndrome (PCOS). It is well known that women with PCOS have lower chances of spontaneous conception as well as lower success with IVF procedures. The mechanisms by which obesity causes lower fertility are not yet fully understood. The aim of the present study was to determine the effect of a lifestyle intervention weight loss program on the expression of the endometrial genes during the window of implantation (WOI). For this purpose, 15 infertile women with obesity and PCOS were included in the study. Endometrial samples were taken during the WOI before and at the end of the program, and RNASeq analysis was performed. There were no significantly differentially expressed genes before and after the weight loss program. We then compared the results of our study with previously published studies on markers of endometrial receptivity. The biomarker genes that were found to be down-regulated during the WOI in previous studies were more down-regulated after the weight loss program in the present study. Furthermore, 25% of the women who achieved the desired 5% or more weight reduction conceived spontaneously. Our study shows that weight loss might positively impact endometrial receptivity. which may lead towards the improved fertility of obese women with PCOS.