Fluorescence in situ hybridization of vertebrate telomere sequence to chromosome ends of the pacific oyster, Crassostrea gigas thunberg

Fluorescence in situ hybridization (FISH) is useful in genomic research. We tested FISH in the Pacific oyster, Crassostrea gigas Thunberg, using metaphase chromosomes prepared from early embryos and alI-human telomere and centromere probes. FISH with the all-human telomere probe produced strong hybridization signals at ends of all oyster chromosomes, suggesting that: (1) chromosomes from embryo preparation are suitable for FISH analysis; and (2) the vertebrate telomere sequence, (T₂AG₃)(n), may be present in telomeres of the Pacific oyster. No interstitial sites were detected for the telomere sequence. FISH with the all-human centromere probe failed to detect any complementary sequences in oyster chromosomes.