Mechanism of KMT5B haploinsufficiency in neurodevelopment in humans and mice.

Pathogenic variants in KMT5B, a lysine methyltransferase, are associated with global developmental delay, macrocephaly, autism, and congenital anomalies (OMIM# 617788). Given the relatively recent discovery of this disorder, it has not been fully characterized. Deep phenotyping of the largest (n = 43) patient cohort to date identified that hypotonia and congenital heart defects are prominent features that were previously not associated with this syndrome. Both missense variants and putative loss-of-function variants resulted in slow growth in patient-derived cell lines. KMT5B homozygous knockout mice were smaller in size than their wild-type littermates but did not have significantly smaller brains, suggesting relative macrocephaly, also noted as a prominent clinical feature. RNA sequencing of patient lymphoblasts and Kmt5b haploinsufficient mouse brains identified differentially expressed pathways associated with nervous system development and function including axon guidance signaling. Overall, we identified additional pathogenic variants and clinical features in KMT5B-related neurodevelopmental disorder and provide insights into the molecular mechanisms of the disorder using multiple model systems

Regional heterogeneity and firms’ innovation: the role of regional factors in industrial R&D in India

This study makes an early attempt to estimate the magnitude and intensity of manufacturing firms’ R&D by Indian states during the period 1991‒2008 and analyses the role of regional factors on firm-level R&D activities. As there is little research on state-wise R&D performance of firms in India, this study serves an important contribution to the academic and policy realm. It has brought out the fact the total manufacturing R&D investment in India is unevenly distributed regionally with a few states accounting for disproportionate share of it. Regional heterogeneity or inter-state disparities in R&D has increased between the 1990s and the first decade of the twenty-first century. In view of this persistent regional heterogeneity in R&D, the study has developed and estimated an empirical model for a sample of 4545 Indian manufacturing firms with R&D facilities located in single state and that explicitly includes regional factors as probable factors affecting R&D. The three-step Censored Quantitle Regression results confirm that regional factors play an important role in shaping the R&D intensity of the sample of firms. This led us to some useful policy suggestions for regional governments to promote local firms’ R&D activities

Mechanism of KMT5B haploinsufficiency in neurodevelopment in humans and mice.

Pathogenic variants in KMT5B, a lysine methyltransferase, are associated with global developmental delay, macrocephaly, autism, and congenital anomalies (OMIM# 617788). Given the relatively recent discovery of this disorder, it has not been fully characterized. Deep phenotyping of the largest (n = 43) patient cohort to date identified that hypotonia and congenital heart defects are prominent features that were previously not associated with this syndrome. Both missense variants and putative loss-of-function variants resulted in slow growth in patient-derived cell lines. KMT5B homozygous knockout mice were smaller in size than their wild-type littermates but did not have significantly smaller brains, suggesting relative macrocephaly, also noted as a prominent clinical feature. RNA sequencing of patient lymphoblasts and Kmt5b haploinsufficient mouse brains identified differentially expressed pathways associated with nervous system development and function including axon guidance signaling. Overall, we identified additional pathogenic variants and clinical features in KMT5B-related neurodevelopmental disorder and provide insights into the molecular mechanisms of the disorder using multiple model systems

Fetal costello syndrome with neuromuscular spindle excess and p.Gly12Val HRAS mutation

International audienc

Prenatal diagnosis of isolated Congenital Heart Defects: results of a prospective study genome-wide high resolution array-CGH versus karyotyping and 22q11 FISH

International audienc

Implication of the SH3TC2 gene in Charcot-Marie-Tooth disease associated with deafness and/or scoliosis: Illustration with four new pathogenic variants

International audienceThe autosomal recessive demyelinating form of Charcot-Marie-Tooth can be due to SH3TC2 gene pathogenic variants (CMT4C, AR-CMTde-SH3TC2). We report on a series of 13 patients with AR-CMTde-SH3TC2 among a French cohort of 350 patients suffering from all type of inheritance peripheral neuropathy. The SH3TC2 gene appeared to be the most frequently mutated gene for demyelinating neuropathy in this series by NGS. Four new pathogenic variants have been identified: two nonsense variants (p.(Tyr970*), p.(Trp1199*)) and two missense variants (p.(Leu1126Pro), p.(Ala1206Asp)). The recurrent variant p.Arg954* was present in 62%, and seems to be a founder mutation. The phenotype is fairly homogeneous, as all these patients, except the youngest ones, presented scoliosis and/or hearing loss