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S Edkins

Publications and source records attributed to S Edkins.

14 recordsLinked to original sources

Mutations in the RSK2(RPS6KA3) gene cause Coffin-Lowry syndrome and nonsyndromic X-linked mental retardation.

We describe three families with X-linked mental retardation, two with a deletion of a single amino acid and one with a missense mutation in the proximal domain of the RSK2(RPS6KA3) (ribosomal protein S6 kinase, 90 kDa, polypeptide 3) protein similar to mutations found in Coffin-Lowry syndrome (CLS). In two families, the clinical diagnosis had been nonsyndromic X-linked mental retardation. In the third family, although CLS had been suspected, the clinical features were atypical and the degree of intellectual disability much less than expected. These families show that strict reliance on classical clinical criteria for mutation testing may result in a missed diagnosis. A less targeted screening approach to mutation testing is advocated.

Amino Acid Sequence↗

The gene for cherubism maps to chromosome 4p16.3.

Cherubism is a rare familial disease of childhood characterized by proliferative lesions within the mandible and maxilla that lead to prominence of the lower face and an appearance reminiscent of the cherubs portrayed in Renaissance art. Resolution of these bony abnormalities is often observed after puberty. Many cases are inherited in an autosomal dominant fashion, although several cases without a family history have been reported. Using two families with clinically, radiologically, and/or histologically proved cherubism, we have performed a genomewide linkage search and have localized the gene to chromosome 4p16.3, with a maximum multipoint LOD score of 5. 64. Both families showed evidence of linkage to this locus. Critical meiotic recombinants place the gene in a 3-cM interval between D4S127 and 4p-telomere. Within this region a strong candidate is the gene for fibroblast growth factor receptor 3 (FGFR3); mutations in this gene have been implicated in a diverse set of disorders of bone development.

Adult↗

A gene for lymphedema-distichiasis maps to 16q24.3.

Lymphedema-distichiasis (LD) is a dominantly inherited syndrome with onset of lymphedema at or just after puberty. Most affected individuals have distichiasis-fine hairs arising inappropriately from the eyelid meibomian glands-which is evident from birth. A study of three families with LD has shown linkage to chromosome 16q24.3, and subsequent analysis of the region for recombinant genes places the locus between D16S422 and D16S3074, a distance of approximately 16 cM. Possible candidate genes in this interval include the N-proteinase for type 3 collagen, PCOLN3; the metalloprotease PRSM1; and the cell matrix-adhesion regulator, CMAR.

Chromosomes, Human, Pair 16↗

Duodenal bile acids in infants with protracted diarrhoea.

Bile acids were estimated in the duodenum of infants with protracted diarrhoea and compared with those in a control group. Significantly lower levels of total bile acids were found in infants with protracted diarrhoea, a finding which may be due to ileal dysfunction. Low concentrations of total bile acids may contribute to the poor nutritional state of these patients by impairing the normal digestion and absorption of dietary fat and fat-soluble vitamins. The absence of deconjugated bile acids in the duodenal juice of most infants with protracted diarrhoea suggests that they do not contribute significantly to the pathophysiology of this disorder.

Bile Acids and Salts↗

Duodenal bile acids in infancy.

Duodenal bile acids have been estimated in three age groups in infancy from birth to 7 months, and age-related changes have been shown. The lowest concentrations of duodenal bile acids occurred in the youngest infants, and increasing concentrations were found with increasing age. Taurine conjugated bile acids predominated in early infancy, while in older infants bile acids were mainly conjugated with glycine. The probable presence of taurolithocholic acid in the duodenal bil of 2 newborns before the establishment of a gastrointestinal microflora remains to be confirmed, but could result either from transplacental passage of secondary bile acids or from endogenous synthesis by the fetal liver.

Age Factors↗