Two genes, BRCA1, located on chromosome 17q21 (5,6), and BRCA2, located on 13q12-13 (7–9), have been shown to predispose to familial breast cancer.
I have no clue, there is nothing else here to support your question.
<span>The sequence of alternation of generation is; gametes->zygote->sporophyte->spores->gametophyte->gametes.
The attached diagram shows clearly this looped cycle. Alternation of generation
occurs in a more advanced land plant that
has distinct
haploid and diploid phases in their life
cycle. The diploid phase usually involves
the sporophyte while the haploid phase involves the gametophyte</span>
What holds the two strands of DNA molecules to each other. Hydrogen Bonds
Eye strain - hope this helped