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目的：研究ＲＢ患者肿瘤及体细胞中Ｒｂ基因点突变的频率、特征及其在肿瘤遗传易感性的传递及肿瘤形成机制中所起的作用。方法：ＳＳＣＰ分析及直接ＤＮＡ序列分析。结果：在３０２例经Ｓｏｕｔｈｅｒｎｂｌｏｔｔｉｎｇ杂交证实无明显Ｒｂ基因缺失或重排的ＲＢ患者的肿瘤或外周血白细胞ＤＮＡ中共发现１８７个Ｒｂ基因点突变。结论：Ｒｂ基因点突变几乎随机分布在整个编码区，常常导致氨基酸密码突变为终止密码，阅读框架移位或ｍＲＮＡ拼接异常，产生缩短了的或缺乏某个外显子编码氨基酸的蛋白质。并以单个碱基取代占绝大多数，缺失或插入突变通常是一个或二个碱基的微小病变。
Objective: To study the frequency and characteristics of Rb gene mutation in tumor and somatic cell of RB patients and its role in the transmission of tumor genetic susceptibility and tumorigenesis. Methods: SSCP analysis and direct DNA sequence analysis. RESULTS: A total of 187 Rb gene point mutations were found in the tumor or peripheral blood leukocyte DNA of 302 patients with RB with no obvious Rb gene deletion or rearrangement confirmed by Southern blotting hybridization. CONCLUSIONS: Point mutations in Rb genes are almost randomly distributed throughout the coding region, often resulting in mutations in the amino acid code such as stop codons, reading frame shifts or mRNA splicing anomalies, resulting in proteins shortened or lacking an exon-encoded amino acid. And take a single base substitution accounted for the vast majority, deletion or insertion mutation is usually one or two small lesions of the base.