Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0025362 (mental retardation)
 15,878 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Mental retardation is believed to be a result of alterations in molecular pathways underlying neuronal processes involved in cognitive functions. It is not fully understood, however, which molecular pathways are critical for cognitive mechanisms. Furthermore, whether mental retardation is a developmental or ongoing disorder of cognitive functions is unknown. Answering these questions will help elucidate the etiology of mental retardation and possibly lead to new therapies. Several recently published studies suggested that mental retardation might be caused by defects in synapse structure and function. Four genes mutated in families with mental retardation encode proteins known as Rho guanine nucleotide exchange factor 6, oligophrenin-1, p21-activated kinase, and guanine dissociation inhibitor 1. Each of these interacts with various guanine nucleotide-binding proteins involved in signaling pathways that regulate the actin cytoskeleton, neurite outgrowth, neurotransmitter release, and dendritic spine morphology. The goal is to understand the roles of these genes in normal cognitive functions.
 ...
PMID:Is mental retardation a defect of synapse structure and function? 1367 16

Gene mapping data indicate that the human X chromosome is enriched in genes that affect both, higher cognitive efficiency and reproductive success. This raises the question whether these functions are ancient, or whether conserved X-linked genes were recruited to new functions. We have studied three X-linked mental retardation (XLMR) genes by RNA in situ hybridization in mouse and in chicken, in which these genes are autosomal: Rho guanine nucleotide exchange factor 6 (ARHGEF6), oligophrenin (OPHN1), and p21 activated kinase 3 (PAK3). In the mouse these genes are specifically expressed in telencephalic regions. Their orthologues in the chicken gave patterns of similar specificity in ancient parts of the brain, i.e. cerebellum and mesencephalon, but were not expressed in the telencephalon. Also in the testes, specific expression was only found in mouse, not in chicken. These data are interpreted such that certain genes on the X chromosome gained novel functions during evolution.
 ...
PMID:Recruitment of old genes to new functions: evidences obtained by comparing the orthologues of human XLMR genes in mouse and chicken. 1731 56