Question

The coding region alone for the important BRCA1 tumor supressor gene in humans contains 5,592 bp (base pairs) of DNA in the coding region. Mutations in the BRCA1 gene associate with breast and ovarian cancer in humans and "carriers" of BRCA1 mutations have a ~50-65% chance of developing breast cancer by age 70.

with the above info alone calculate (i) the predicted number of amino acids for the encoded BRCA1 protein, and (ii) predict the molecular weight of the BRCA1 protein in kDa, using the average amino acid molecular weight.

Answer 1

(i) the predicted number of amino acids in BRCA1 protein = size of DNA in bases /3=5592/3= 1864

(ii) predicted molecular weight of BRCA1= no of amino acid X 0.11 KDa ( as molecualr weight of 1 amino acid = 0.11 kDa

                                                         = 1864 X 0.11

                                                         =205.04 KDa