title: A twin study of the structure of human hair medulla.
abstract: The genetic basis of hair medulla was studied by the twin method. Hair samples from 17 pairs of monozygotic (9 female and 8 male), 23 pairs of like-sex dizygotic (6 female and 17 male) and 8 pairs of unlike-sex dizygotic twins were utilized and the number of hair strands examined was 9,600. The mean intrapair differences indicate the presence of a strong genetic basis of the character concerned.
mesh_terms: D005260:Female; D005823:Genetics; D006197:Hair / Q000648:ultrastructure*; D006801:Humans; D008297:Male; D011247:Pregnancy; D014427:Twins; D014429:Twins, Dizygotic; D014430:Twins, Monozygotic