遗传性儿童脊肌肉萎缩症(spinal muscular atrophy,SMA)是囊性纤维性变以外的第二位最常见的常染色体隐性遗传病。按发病年龄可分为Ⅰ型(急性婴儿型),Ⅱ型(中间型)及Ⅲ型(青少年型),其中又以Ⅰ型最为常见及严重,患儿常因呼吸困难死于2岁以内,故难以研究。导致Ⅱ及Ⅲ型的基因已定位于5 q12-q14处。作者在此报道对Ⅰ型疾病的连锁分析。通过对至少各有一个Ⅰ型疾病患儿及一个正常儿童的25个家系进行连锁分析,发现Ⅰ型基因位点与D5S39标记间的Z=2.36,θ=0.00(X~2=10.87,P<0.005),说明此突变基因与D5S39标记紧密连锁。此发现 Hereditary child spinal muscular atrophy (SMA) is the second most common autosomal recessive disease other than cystic fibrosis. According to the age of onset can be divided into type Ⅰ (acute infant type), type Ⅱ (intermediate type) and type Ⅲ (adolescent type), of which type Ⅰ is the most common and serious, often due to respiratory distress in children died within 2 years of age, It is difficult to study. The type II and type III genes have been mapped at 5 q12-q14. The authors report here on a linkage analysis of type I disease. A linkage analysis of 25 pedigrees with at least one type I disease and one normal child found that Z = 2.36 between the type I locus and the D5S39 marker, θ = 0.00 (X ~ 2 = 10.87, P < 0.005), indicating that the mutant gene is closely linked with the D5S39 marker. This discovery