A segment of DNA produces methionine, threonine, histidine, aspartate, and glycine when translated. A substitution mutation occurs and causes the synthesis of the segment as shown. New DNA Strand: 3' – TACAGGGTGCTACCCACT – 5' Which is the new peptide chain when the new DNA segment is translated?

In gene expression, DNA, which is the genetic material is transcribed into mRNA, which is subsequently translated into a amino acid sequence (peptide). The transcription of DNA into mRNA follows complementary base pairing rule i.e. A-U, G-C, T-A.

The nucleotide sequence in the mRNA molecules are read in group of three nucleotide bases called CODONS. Each codon specifies an amino acid.

According to this question, a segment of DNA produces methionine, threonine, histidine, aspartate, and glycine when translated, however, a substitution mutation occurs and causes the synthesis of the segment as shown: 3' – TACAGGGTGCTACCCACT – 5'

The mRNA sequence from this mutated DNA sequence is as follows: AUGUCCCACGAUGGGUGA

During translation, the following codons specify the following amino acids:

AUG - methionine

UCC - Serine

CAC - Histidine

GAU - Aspartate

GGG - Glycine

UGA - Stop codon

Based on this, the new peptide chain when the new DNA segment is translated will be: Methionine- Serine- Histidine- Aspartate- Glycine- Stop