title: Segregation and sporadic cases of Duchenne muscular dystrophy in the Henan Province, China.
abstract: In the Henan province, China, the segregation ratio of Duchenne muscular dystrophy, estimated through classical segregation analysis on 103 sibships, is p = 0.462, and the maximum likelihood proportion of sporadic cases is x = 0.264. These figures are in agreement with the results of segregation analysis on 1,800 families from different countries; also, the Henan population shows a slight segregation distortion and lacks a fraction of the sporadic cases predicted under mutation-selection equilibrium. Although not statistically significant, the downward departure of the estimated parameters from their expectations under the mendelian equilibrium hypothesis (p = 0.5; x = 0.333) confirms an anomalous segregation pattern for Duchenne muscular dystrophy. A possible role of germinal mosaicism in concealing a fraction of sporadic cases is discussed.
authors.affiliation: Shanghai Medical University, People's Republic of China.
authors.forename: W M
authors.initials: WM
authors.lastname: Fu
authors.forename: G
authors.initials: G
authors.lastname: Barbujani
mesh_terms: D002681:China / Q000453:epidemiology; D005787:Gene Frequency; D005828:Genetics, Population; D006801:Humans; D016013:Likelihood Functions; D008297:Male; D009136:Muscular Dystrophies / Q000235:genetics*