One cause of colour blindness is a change in the DNA sequence of a gene. This results in the production of a different protein in cone cells in the retina of the eye. Explain how a change in the DNA sequence of a gene can result in the production of a different protein – 10019

Q1.

One cause of colour blindness is a change in the DNA sequence of a gene.

This results in the production of a different protein in cone cells in the retina of the eye.

Explain how a change in the DNA sequence of a gene can result in the production of a different protein.

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Tanvi Iyer says:

July 22, 2025 at 6:05 am

A mutation is a change in the DNA sequence. This change affects the sequence of bases in the mRNA, which is made from the DNA during transcription in the nucleus. The mRNA carries this new sequence to the ribosome, where translation takes place. During translation, each group of three bases (a codon) is read, and the correct amino acid is added by a tRNA molecule. If the mRNA sequence has changed, this may result in a different amino acid being added to the polypeptide chain.

This change in amino acid sequence can affect how the protein folds, which means it may change the shape and function of the final protein. For example, if the protein is meant to help a cone cell detect coloured light in the eye, the mutation could stop it from working properly, so the cone cell can’t detect the light as it should.

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