[The distribution of abnormal hemoglobins in the silk road region of China].

215,785 individuals living in the Silk Road region of China were surveyed for abnormal hemoglobins (Hbs). Among them, 695 carriers were detected. The average incidence of abnormal Hbs was 3/22 and the frequencies of abnormal Hbs among 12 nationalities reached 0.15/1000-12.17/1000. The primary structural analyses were made in 271 persons, and 24 variants [13 alpha-chain variants and 11 beta-chain variants] were identified. HbJ Tashikuergan and Hb Tianshui were discovered the first time in the world. HbS, Hb Bunbury, Hb Setif and HbI Philadelphia were not found previously in the Chinese population. Three variants, i.e. HbD Punjab, HbG Taipei and HbG Coushatta occurred at the highest frequencies and showed a gradient distribution along the Silk Road, suggesting that they may originate from Caucasians in Central Asia, Han in the Yellow River valley, and the ancient nomadic minorities of China in Mongolia Plateau respectively. The frequencies of other variants were quite low. Some were probably imported from other countries and areas, and some arose from independent mutations. The data from many variants support the movements of various populations in this area, as reported in numerous historical documents. It is indicated that the Silk Road promoted the national fusion among the Chinese nationalities, Mongolian and Caucasian races.