THE TELOMERE-ASSOCIATED DNA FROM HUMAN-CHROMOSOME 20P CONTAINS A PSEUDOTELOMERE STRUCTURE AND SHARES SEQUENCES WITH THE SUBTELOMERIC REGIONS OF 4Q AND 18P
I. Chute et al., THE TELOMERE-ASSOCIATED DNA FROM HUMAN-CHROMOSOME 20P CONTAINS A PSEUDOTELOMERE STRUCTURE AND SHARES SEQUENCES WITH THE SUBTELOMERIC REGIONS OF 4Q AND 18P, Genomics, 46(1), 1997, pp. 51-60
The human chromosome 20p telomere has been cloned on a yeast artificia
l chromosome (YAC). The telomere-associated DNA contains an interstiti
al tract of (TTAGGG)(n) telomeric repeats 60 kb in from the chromosome
end. Frequent truncation of the YAC clone was observed due to resolut
ion of the internal telomeric array into a telomere. The 20p internal
telomeric repeat tract is flanked on its centromeric side by telomere-
associated repeated sequences that have previously been found adjacent
to terminal telomeric repeat arrays, The pseudotelomere structure of
the 20p subtelomeric region is similar to the structure of some yeast
subtelomeric regions where these sequences act as substrates for recom
binational repair of chromosome ends that have lost their terminal tel
omeric repeat arrays, Sequences flanking the telomeric end of the inte
rnal (TTAGGG)(n) repeat array on 20p are found adjacent to three other
subtelomeric (TTAGGG)(n) tracts on 4q, 18p, and an unknown. chromosom
e end, respectively. These shared sequences provide evidence of exchan
ge between nonhomologous chromosomes in humans, (C) 1997 Academic Pres
s.