期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1992
卷号：89
期号：4
页码：1354-1357
DOI：10.1073/pnas.89.4.1354
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Tomato telomeres are composed of a terminal 7-base-pair tandem repeat and a closely liked 162-base-pair subtelomeric repeat (TGRI). Together, these repeats account for 2% of the total chromosomal DNA. Pulsed-field gel electrophoresis has been used to examine the long-range physical structure of these arrays in closely related varieties, and we report here that these arrays are undergoing heritable changes at a frequency as great as 2% per generation. Moreover, comparisons with other known hypervariable probes (e.g., human minisatellites and M13 sequences) revealed that telomeric sites are more variable than any other known region of the plant genome and can be used to distinguish closely related plant varieties (tomato and melon) that are otherwise very similar at the DNA level. The fact that the polymorphisms are inherited in a mendelian fashion suggests applications in genetic mapping of telomeres and identification of varieties.
