BRAINCAKEGene Linkage
Each chromosome carries hundreds or thousands of genes. Genes found on the same chromosome are said to be linked (autosomal linkage when the chromosome is not a sex chromosome).
Linked genes do not assort independently. Because they are on the same chromosome, the alleles on that chromosome tend to be passed into the same gamete and inherited together. So Mendel's law of independent assortment does not apply to them.
Worked example: genes A and B are linked. A fly has A and B on one chromosome and a and b on its homologue (written AB/ab). Without crossing over it makes only two gamete types, AB and ab, instead of the four (AB, Ab, aB, ab) expected for unlinked genes.
Sign in free to see the rest of this lesson, the R.E.C.I.P.E. recall steps and the quiz
BrainCake is free. Make an account in seconds and pick up where this page stops.
More in Genetic Information
- Probability
- Chi-Squared Test
- Chi-Squared Test - Monohybrid Crosses
- Chi-Squared Test- Dihybrid Crosses
- Identifying Linked Genes
- Chromosome Mapping
- Sex-Linkage
- Pedigree Diagrams
All 30 lessons in Genetic Information · All Edexcel A-level Biology topics