The protein product, FMRP, is highly expressed in neurons of the normal mammalian brain, and absent or in low levels in leukocytes from individuals with fragile X (FraX)-associated mental impairment.
Pathogenicity of MEF2C overexpression is still unclear as only four patients with mild intellectual deficiency carrying 5q14.3 microduplications containing MEF2C are described in the literature.
Small molecule inhibition of DYRK1A activity in the brain may provide an avenue for pharmaceutical intervention of mental impairment associated with AD and other neurodegenerative diseases.
Interestingly, the patient with decreased KIAA2022 expression had only mild ID with severe language delay and repetitive behaviors falling in the range of an autism spectrum disorder (ASD).
Missense variants of GRIN1, GRIN2A, and GRIN2B cause similar syndromes with varying severity of intellectual impairment, autism, epilepsy, and motor dysfunction.
Fragile X syndrome (FXS) is an inherited intellectual impairment that results from the loss of fragile X mental retardation protein (FMRP), an mRNA binding protein that regulates mRNA translation at synapses.
We conclude that the excess of intermediate and premutation sized alleles for FRAXA may well be a contributing factor to the boys' mental impairment, while that for FRAXE may be a chance finding.
Fragile X syndrome (FXS) is an inherited intellectual impairment that results from the loss of fragile X mental retardation protein (FMRP), an mRNA binding protein that regulates mRNA translation at synapses.
A relationship between FRAXE and non-specific mental impairment is strongly suggested by the occurrence in these families of more mentally impaired male and female carriers, after removal of index cases, than could reasonably be expected by chance.
ARG1-deficient patients exhibit hyperargininemia with spastic paraparesis, progressive neurological and intellectual impairment, persistent growth retardation, and infrequent episodes of hyperammonemia, a clinical pattern that differs strikingly from other urea cycle disorders.
Three additional families with likely pathogenic KIAA2022 mutations were discovered within the frame of systematic parallel sequencing of familial cases of XLID or in the context of routine array-CGH evaluation of sporadic intellectual deficiency (ID) cases.
Intragenic rearrangements in X-linked intellectual deficiency: results of a-CGH in a series of 54 patients and identification of TRPC5 and KLHL15 as potential XLID genes.
SPG11, an AR-HSP (synonym: HSP11), is a complicated HSP associated with a slowly progressive spastic paraparesis, mental impairment and the development of a thin corpus callosum (TCC) during the course of the disease.
MAOB deficient patients exhibit normal clinical characteristics and behavior, while MAOA deficient patients have borderline intellectual deficiency and impaired impulse control.
The 3 tumor suppressor genes KCTD11, DLG4, and GPS2, in addition to the GABARAP gene, have a known or suspected function in neuronal development and are candidates for causing mental impairment in our patients.
Our data indicate that astrocytes expressing mutant HRAS dysregulate cortical maturation during development as shown by abnormal extracellular matrix remodeling and implicate excessive astrocyte-to-neuron signaling as a possible drug target for treating mental impairment and enhancing neuroplasticity.
Forty-one participants with ASD and no intellectual impairment, aged 12-17 years, were randomly assigned to an immediate intervention or a delayed-intervention group.