well most people seem to think so, but my mom is actually a 44DDD or DDD44 or watever! Shes been big since she was 12 then theres me...the complete opposite! At 14 my mom was 98 pounds 5'6 and had size C-D boobs! At 14 i was 96 pounds 5'4 and had...when i was 14 i had no boobs. at all. not even trainers bra was needed for moi! Unexplainable eh?

Genetics is a factor in breast size but only one of many factors. My sister has the same breast size as our mother, but I don't. That's how it is, genetics may work for you or it may not, but if it doesn't work for you it doesn't then follow that genes are irrelevant. Genes are always a factor, they just can't alone determine what your breast size is going to be. For my sister the genes worked well for breast size, as she has the same bra size exactly as mother, but I wasn't lucky in that department.