LOD score

In genetics , the LOD score is used as a statistical estimate of the likelihood of whether two loci (gene locations) on the same chromosome are close to each other and are thus inherited as coupled.

LOD stands for logarithm of the odds or logarithmic odds ratio .

A LOD score greater than three is usually viewed as an indicator of gene linkage . LOD = 3 means that if two gene locations are observed together, the probability is 1000 times greater (logarithm to base 10) that the two gene locations were transferred together instead of a random event due to genetic linkage. The multilocus coupling analysis can be based on two types of information: pairwise LOD score , in which only two loci are taken into account at once, and on multipoint , in which more than two loci are taken into account.

LOD scores are an important statistical parameter in the identification of quantitative trait loci , i.e. chromosome segments that influence the expression of a certain quantitative trait.