Replication delay along FRA7H, a common fragile site on human chromosome 7, leads to chromosomal instability.

ABSTRACT: Common fragile sites are specific chromosomal loci that show gaps, breaks, or rearrangements in metaphase chromosomes under conditions that interfere with DNA replication. The mechanism underlying the chromosomal instability at fragile sites was hypothesized to associate with late replication time. Here, we aimed to investigate the replication pattern of the common fragile site FRA7H, encompassing 160 kb on the long arm of human chromosome 7. Using in situ hybridization on interphase nuclei, we revealed that the replication of this region is initiated relatively early, before 30% of S phase is completed. However, a high fraction ( approximately 35%) of S-phase nuclei showed allelic asynchrony, indicating that the replication of FRA7H is accomplished at different times in S phase. This alle

SUBMITTER: Hellman A 

PROVIDER: S-EPMC85809 | biostudies-literature | 2000 Jun

REPOSITORIES: biostudies-literature