Suppose that rat liver expresses a protein called Yorfavase. This enzyme is composed of 192 amino acid residues, and thus the coding region of the yfg gene consists of 576 bp. However, the rat genome database indicates that the yfg gene consists of 1440 bp. Select which type of DNA does not contribute to the additional 864 bp found in the yfg gene.
O O O 5-end untranslated regulatory region centromeric DNA
DNA coding for a signal sequence noncoding intron O promoter sequence

Genes are responsible for formation of proteins. A codon produces a single amino acid and it comprises of three base pairs. The whole DNA of organism does not contribute to encode protein. There are sequences in DNA that does not contribute in coding known as non-coding DNA and perform different functions. These may include the O O O 5-end, DNA coding for a signal sequence, noncoding intron and O promoter sequence .

The centromere is the part of DNA that links the sister chromatids. The centromere is not converted to mRNA or proteins. It is also not involved in regulation of genes. So it did not contribute to 864 bp found in the yfg gene.