0000000001030373

AUTHOR

Kosuke Izumi

NFIB Haploinsufficiency Is Associated with Intellectual Disability and Macrocephaly

The nuclear factor I (NFI) family of transcription factors play an important role in normal development of multiple organs. Three NFI family members are highly expressed in the brain, and deletions or sequence variants in two of these, NFIA and NFIX, have been associated with intellectual disability (ID) and brain malformations. NFIB, however, has not previously been implicated in human disease. Here, we present a cohort of 18 individuals with mild ID and behavioral issues who are haploinsufficient for NFIB. Ten individuals harbored overlapping microdeletions of the chromosomal 9p23-p22.2 region, ranging in size from 225 kb to 4.3 Mb. Five additional subjects had point sequence variations c…

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The clinical and molecular spectrum of QRICH1 associated neurodevelopmental disorder

De novo variants in QRICH1 (Glutamine-rich protein 1) has recently been reported in 11 individuals with intellectual disability. The function of QRICH1 is largely unknown but it is likely to play a key role in the unfolded response of endoplasmic reticulum (ER) stress through transcriptional control of proteostasis. In this study, we present 27 additional individuals and delineate the clinical and molecular spectrum of the individuals (n=38) with QRICH1 variants. The main clinical features were mild to moderate developmental delay/intellectual disability (71%), non-specific facial dysmorphism (92%) and hypotonia (39%). Additional findings included poor weight gain (29%), short stature (29%)…

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