Phenotypic variation in a family with mutations in two Hirschsprung-related genes (RET and endothelin receptor B).
Hirschsprung disease is a congenital malformation affecting 1 in 5000 live births. The absence of parasympathetic neuronal ganglia (Meissner, Auerbach) in the hindgut results in poor coordination of peristaltic movement, and a varying degree of constipation. Four different genes have been implicated in the pathogenesis of Hirschsprung disease: the RET tyrosine kinase receptor gene; one of its ligands, the glial cell line-derived neurotrophic factor (GDNF) gene; the endothelin receptor B (EDNRB) gene; and its ligand, endothelin-3 (EDN3). Recently, combinations of mutations in two of these genes (RET and GDNF) have been reported in Hirschsprung patients. We report a family with missense mutations in both the RET gene (R982C) and the EDNRB gene (G57S). In this family, three out of five members have the two mutations, but only one, a boy, has the Hirschsprung disease phenotype. This illustrates the complexity of the molecular background of Hirschsprung disease.
Department of Molecular Medicine, Karolinska Hospital, Stockholm, Sweden. Par-Johan.Svensson@cmm.ki.se
P J
PJ
Svensson
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Anvret
M L
ML
Molander
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Nordenskjöld
D004262:DNA Restriction Enzymes / Q000378:metabolism; D029721:Drosophila Proteins; D005260:Female; D014644:Genetic Variation; D051097:Glial Cell Line-Derived Neurotrophic Factor Receptors; D006627:Hirschsprung Disease / Q000235:genetics*; D006801:Humans; D008297:Male; D009154:Mutation; D010375:Pedigree; D010641:Phenotype; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D051096:Proto-Oncogene Proteins c-ret; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics*; D044023:Receptor, Endothelin B; D017466:Receptors, Endothelin / Q000235:genetics*
D029721:Drosophila Proteins; D051097:Glial Cell Line-Derived Neurotrophic Factor Receptors; D011518:Proto-Oncogene Proteins; D044023:Receptor, Endothelin B; D017466:Receptors, Endothelin; D051096:Proto-Oncogene Proteins c-ret; D020794:Receptor Protein-Tyrosine Kinases; C416649:Ret protein, Drosophila; D004262:DNA Restriction Enzymes