Genetic Concepts: Match the Column

Correct Answer: 1-e, 2-d, 3-b, 4-a, 5-c

From the notes (Causes of genetic correlation and breeding systems):

• 1. Pleiotropy (e) = Permanent cause of genetic correlation: One gene affects multiple traits simultaneously. Examples: sickle cell anemia gene, halothane gene in pigs, double muscling gene in cattle. Since the gene itself causes the correlation, it is permanent.
• 2. Linkage (d) = Transient/temporary cause of genetic correlation: Two genes on the same chromosome appear correlated but can be separated by crossing over over generations — hence transient.
• 3. Inbreeding (b) = Increases homozygosity: Mating of related individuals → progressive increase in homozygosity → inbreeding depression in fitness traits.
• 4. Outbreeding (a) = Increases heterozygosity: Mating of unrelated individuals → increases heterozygosity → heterosis/hybrid vigour.
• 5. Panmixia (c) = Random mating: As defined in Hardy-Weinberg law — gene and genotypic frequencies remain constant under panmixia.