Doctors analyse DNA from tumour cells to identify whether tumour-genome profile R is present or absent.
Patients with the same type of tumour were selected at random from several hospitals. They received treatment A or treatment B for 12 weeks.
The table shows the results.
| Tumour-genome profile | Treatment | Number of patients | Patients whose tumour decreased in size (%) | Patients with serious side effects (%) |
|---|---|---|---|---|
| R present | A | 120 | 78 | 24 |
| R present | B | 116 | 52 | 8 |
| R absent | A | 30 | 40 | 20 |
| R absent | B | 32 | 72 | 9 |
Evaluate whether doctors should use tumour-genome profile R to help choose between treatment A and treatment B.
96 exam-style questions on Edexcel GCSE Biology 3.4 Variation and the Human Genome Project, covering 3.4.1 Causes of variation, 3.4.2 Outcomes of the Human Genome Project, 3.4.3 Genetic variation within a population, and 3.4.4 Effects of genetic mutations on phenotype. Each one has a worked solution and a mark scheme showing where the marks go.