ISSN:
1432-1203
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Summary Restriction fragments from the fraction of small polydisperse circular DNA (spcDNA) were cloned in pBR322. The spcDNA was prepared from cell cultures derived from an angiofibroma of a patient with tuberous sclerosis (TS). Such cultures have been shown previously to contain increased amounts of spcDNA. Four cloned spcDNA fragments containing single-copy sequences were chosen to characterize the homologous chromosomal DNA segments by restriction analysis. When used as hybridization probes, these four fragments generate well-defined nonvariable patterns in the chromosomal DNA from healthy donors. The restriction patterns obtained with one of the fragments (D-C4) can best be interpreted by assuming the presence of two copies of the homologous sequences in chromosomal DNA. A second sequence, A-B4, occurs at least 30–50 times in the haploid human genome. In both cases the duplicated regions span relatively large segments of DNA.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00291164
