How does recombination influence LD across generations?

How does recombination influence LD across generations?

• A. Recombination breaks down associations between alleles at different loci, reducing LD over time.
• B. Recombination increases LD over time.
• C. Recombination does not affect LD.
• D. Recombination only affects LD within a single locus.

Answer: (C)

Recombination dissolves non-random associations between alleles at different loci over generations. During meiosis, it shuffles alleles, creating new haplotypes and breaking up existing allele combinations. Because linkage disequilibrium measures how often certain allele pairs co-occur, this reshuffling reduces that non-random association over time. If the recombination fraction between two loci is r, the leftover LD after one generation is roughly multiplied by (1 − r), so LD decays toward zero across generations. The farther apart the loci are, the larger r is, and the faster LD declines. So recombination does affect LD and tends to reduce it over time, rather than leaving it unchanged or increasing it.

Recombination dissolves non-random associations between alleles at different loci over generations. During meiosis, it shuffles alleles, creating new haplotypes and breaking up existing allele combinations. Because linkage disequilibrium measures how often certain allele pairs co-occur, this reshuffling reduces that non-random association over time. If the recombination fraction between two loci is r, the leftover LD after one generation is roughly multiplied by (1 − r), so LD decays toward zero across generations. The farther apart the loci are, the larger r is, and the faster LD declines. So recombination does affect LD and tends to reduce it over time, rather than leaving it unchanged or increasing it.