Total genome scan analysis in a single extended family for primary nocturnal enuresis: Evidence for a new locus (ENUR3) for primary nocturnal enuresis on chromosome 22q11

Objective: In this study we focussed on a single large family to maximize the possibility of recognizing a single locus. This family alone could raise a lod score above 3, i.e. sufficient by tradition for assignment of a locus. Methods: The family consists of 11 children and 26 grandchildren in whom monosymptomatic primary nocturnal enuresis (PNE) is segregating in three generations. A genome scanning with about 800 polymorphic marker systems was used to localize a chromosome area for the trait and to narrow down the candidate region. Results: Total genome scan and multipoint analysis map PNE to chromosome 22 between the markers D22S446 and D22S343 with a multipoint lod score of 4.51. Conclusion: In the candidate area for PNE, the gene GNAZ is mapped. GNAZ has a transducin function in eye and brain and is an obvious candidate gene for PNE.