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Pearson Edexcel IAL Biology 2.14 DNA replication errors & mutations

Practise explaining mutation types, their effects on protein sequence, and links to disorders, cancer risk or no observable change.

Syllabus
First assessment 2019
Course
Biology YBI11
Level
AS

Exam points

  • distinguish substitution, insertion and deletion by their effect on a DNA base sequence
  • explain how codon changes can remove or alter amino acids in a protein
  • link DNA replication errors or mutation accumulation to cancer or inherited disorder contexts

2.14—DNA replication errors and mutations question 1

[Maximum number: 1]

Sickle cell disease is caused by a gene mutation affecting the β\beta-globin chain of haemoglobin.

The mutation occurs in the seventh triplet code of this gene.

This mutation results in the amino acid Glu being replaced with the amino acid Val.

The table shows the sequence of bases in the first part of the DNA in a person who does not have sickle cell disease. It also shows the corresponding sequence of amino acids in the β\beta-globin chain.

Table for Question 2.14—DNA replication errors and mutations question 1 — Edexcel A-Level Biology AS

Name the type of mutation that causes sickle cell disease.

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