Molecular Genetics
In affected members of 4 Pakistani families with leukonychia totalis mapping to chromosome 3p22-21.3, 2 of which demonstrated autosomal recessive inheritance and 2 of which were consistent with autosomal dominant inheritance, Kiuru et al. (2011) analyzed candidate genes and identified homozygosity or heterozygosity for nonsense, splice site, and missense mutations in the PLCD1 gene (602142.0001-602142.0004). None of the mutations were found in 130 unrelated population-matched controls. Kiuru et al. (2011) noted that the phenomenon of recessive and dominant mutations in the same gene resulting in a similar phenotype is rare.