Although it was initially thought that MECP2 pathogenic mutations in males were not compatible with life, starting from 1999 about 60 male patients have been identified and their phenotype varies from severe neonatal encephalopathy to mild intellectual disability.
Here we identified dominant mutations in the gene encoding the transcriptional repressor and MeCP2 interactor switch-insensitive 3 family member A (SIN3A; chromosome 15q24.2) in individuals who, in addition to mild intellectual disability and ASD, share striking features, including facial dysmorphisms, microcephaly and short stature.
Molecular analysis has allowed the phenotype of MECP2 mutations to be broadened beyond RTT to include girls who have mild mental retardation, autism, and an Angelman syndrome phenotype, as well as males with severe encephalopathy.
Mutations in the structural exosome gene EXOSC2 cause a distinct syndrome that includes retinitis pigmentosa, hearing loss, and mild intellectual disability.
Here we identified dominant mutations in the gene encoding the transcriptional repressor and MeCP2 interactor switch-insensitive 3 family member A (SIN3A; chromosome 15q24.2) in individuals who, in addition to mild intellectual disability and ASD, share striking features, including facial dysmorphisms, microcephaly and short stature.
Here, we report the identification of a novel homozygous variant in PTEN, NM_000314.4; c.545T>C; p.Leu182Ser, in two adolescent siblings with severe macrocephaly and mild intellectual disability.
That the deletion encompassed FGD1 (exons 2-8) explains the Aarskog features while the deletion of PHF8 most likely explains the cleft palate and mild intellectual disability.
Among Noonan syndrome patients with a confirmed mutation, mild intellectual disability tended to be more common in patients with PTPN11 mutation than in those with SOS1 mutation.
In conclusion, a novel p.W170S mutation in the extracellular ligand binding domain of glycine receptor α1 subunit was detected in patients with hyperekplexia and mild mental retardation.
Although the deletions did not involve the neurofibromatosis type 1 (NF1) gene, they overlap with long-range deletions of the NF1 region which have been encountered in a small group of NF1 patients with more severe MR.
We identified a homozygous missense mutation in the noncatalytic subunit (RAB3GAP2) of RAB3GAP that results in abnormal splicing in a family with congenital cataracts, hypogonadism, and mild mental retardation (Martsolf syndrome).
An autosomal recessive limb girdle muscular dystrophy (LGMD2) with mild mental retardation is allelic to Walker-Warburg syndrome (WWS) caused by a mutation in the POMT1 gene.
Recently, we described a novel form of recessive limb girdle muscular dystrophy with mild mental retardation, associated with an abnormal alpha-dystroglycan pattern in the muscle, suggesting a glycosylation defect.
Recently, we have shown that the majority of the X-linked families with infantile spasms carry mutations in the aristaless-related homeobox gene (ARX), which maps to the Xp21.3-p22.1 interval, and that the clinical picture in these patients can vary from mild mental retardation to severe ISSX with additional neurological abnormalities.
Missense mutations and distal truncations consistent with partial loss of FLN1 function cause familial BPNH with the classical clinical phenotype including epilepsy and mild mental retardation, if any.
Physical mapping of the breakpoints of a pericentric inversion of the X chromosome (46,X,inv[X][p21q27]) in a female patient with mild mental retardation revealed localization of the Xp breakpoint in the IL1RAPL gene at Xp21.3 and the Xq breakpoint near the SOX3 gene (SRY [sex determining region Y]-box 3) (GenBank accession number NM_005634) at Xq26.3.
We determined the CGG repeat length and AGG interruptions in the FMR1 gene in normal Chinese subjects and patients with infantile autism and mild mental retardation.
A syndrome has been observed in a kindred with deficient activity of hypoxanthine-guanine phosphoribosyltransferase in which affected hemizygotes have had mild mental retardation, a spastic gait, pyramidal tract signs, shortness of stature, proximally placed thumbs and clinodactyly of the fifth fingers.