Identification of individuals affected by ARH and WH
The material for this study was collected during a field expedition
to the Volga-Ural region of Russia. In total, we observed
119 affected individuals with signs of hypotrichosis. All
affected individuals belong to either the Chuvash ethnic group
(of the Turkic linguistic group) from Chuvash Republic or the
Mari group (Finno-Ugric group) from Mari El Republic. All
ascertained individuals underwent a detailed clinical examination
including a physical examination, light microscopy of
hairs, trichogram, and hair density evaluation. Among affected
individuals, high interfamily and intrafamily polymorphism
was observed. Nevertheless, based on the clinical examination,
two groups of affected individuals were clearly evident.
The majority of affected individuals (116) had a typical
phenotype of hypotrichosis 7 (MIM: 604379) (Figure 1). The
other group included an affected individual from a nonfamilial
case #041 and a family #002 with two affected
individuals and their healthy parents. In spite of the phenotypic
similarity with the hypotrichosis 7 group, several differences
were noted.