Characterization of the telomere regions of scleractinian coral, Acropora surculosa.

Terminal ends of vertebrate chromosomes are protected by tandem repeats of the sequence (TTAGGG). First thought to be vertebrate specific, (TTAGGG)( n ) has recently been identified in several aquatic invertebrates including sea urchin (Strongylocentrotus purpuratus), bay scallop (Argopecten irradians), and wedgeshell clam (Donax trunculus). We analyzed genomic DNA from scleractinian corals, Acropora surculosa, Favia pallida, Leptoria phrygia, and Goniastrea retiformis to determine the telomere sequence.

ERBB2, TBX2, RPS6KB1, and MYC alterations in breast tissues of BRCA1 and BRCA2 mutation carriers.

Breast cancer risk is greatly increased in women who carry mutations in the BRCA1 or BRCA2 genes. Because breast cancer initiation is different between BRCA1/2 mutation carriers and women who do not carry mutations, it is possible that the mechanism of breast cancer progression is also different. Histopathologic and genetic studies have supported this hypothesis.

The 17q23 amplicon and breast cancer.

A novel region of amplification in breast tumors was recently identified on chromosome 17q23. Extensive mapping of the amplicon by Southern blotting and fluorescence in situ hybridization (FISH) in breast cancer cell lines determined that the amplicon can be up to 4 Mbp in size and may contain 50 genes. Copy number analysis at 50-75 kb resolution in breast cancer cell lines and breast tumors identified several independently amplified regions within the amplicon, suggesting that a number of genes are selected for amplification because they independently contribute to tumor formation and progression.

TBX2 is preferentially amplified in BRCA1- and BRCA2-related breast tumors.

The chromosome 17q23 region is frequently amplified in breast tumors. Gain of the region is present in 50% of BRCA1-associated breast tumors and 87% of BRCA2-associated breast tumors. The amplification frequency of the RPS6KB1 and TBX2 oncogenes from this amplicon was compared in 27 BRCA1 and BRCA2 mutant breast tumors, 15 breast tumors from high-risk patients with no BRCA1 or BRCA2 mutations, and 62 matched sporadic breast tumor controls.