NuMA is a structural element in maintaining nuclear integrity. A critical spindle pole-associated mechanism, called the END (Emi1/NuMA/dynein-dynactin) network, spatially restricts APC/C activity in early mitosis. The entire coding region and exon-intron boundaries of NuMa were screened in 92 familial breast cancer patients. But the results do not support the role of NuMA variants as breast cancer susceptibility alleles.