[A typical cases of X-linked anhidrotic ectodermal dysplasia and a diagnosis of carriers].

A typical case of X-linked anhidrotic ectodermal dysplasia (AED) aged 19 year-old-male was discussed in detail, and a diagnosis of carriers of AED with his elder sister aged 24 years just before her marriage and mother was carried out. It seemed that the presence of 6 items of manifestation were important for diagnosis of carriers of AED without any evident symptoms. These were (1) abnormal teeth, (2) dissociation of dermatoglyphics, (3) hypohidrosis, (4) anhidrotic patchy distribution, (5) the lines of Blaschko and (6) expansion of distance between sweat pores. His mother was able to be diagnosed as a carrier of AED by having all of the 6 items. It was confirmed that his sister was not a carrier of AED, since she had none of the 6 items and yet her probability of being a carrier of AED was 1.5625% due to Lyon's hypothesis.