Practice question

LOD transformation uses base 10 logarithm, so LOD = log10[Odds]. Inverting logarithm gives Odds = 10^LOD. Therefore LOD 3 corresponds to 10^3 = 1000, meaning data observation is one thousand times more probable if loci are linked at estimated recombination fraction than if unlinked. This odds interpretation motivated choice threshold because random human genome loci have prior 50:1 probability unlinked, thus 1000:1 yields genome-wide significance approx p 0.05 after accounting multiplicity. LOD -2 similarly corresponds to 100:1 odds against linkage, serving exclusion criterion.