Genetic linkage and mapping

This session centres on Genetic Linkage and Mapping, offering a structured look at the concept of genetic linkage, explaining how genes close together on chromosomes are often inherited together and how this principle underpins genetic mapping. We will discuss how recombination frequency reflects the distance between genes, allowing researchers to construct genetic maps and locate genes associated with specific traits. The lecture will highlight the applications of linkage mapping in medical and agricultural genetics and explore how technological advances have improved the resolution and utility of genetic maps. Finally, we will touch on the integration of linkage analysis with other genomic approaches to deepen our understanding of genome structure and trait inheritance.. Genetic linkage refers to how genes physically close together on the same chromosome tend to be inherited together during meiosis. While Mendelian genetics predicts independent assortment for genes on different chromosomes, nearby genes on the same chromosome do not always assort independently. These “linked genes” are usually inherited together since crossover is less likely to separate them. Linkage is key to genetic mapping, as it reveals the relative positions of genes by observing how traits co-segregate in families or breeding populations. During meiosis, homologous chromosomes exchange segments through recombination. The frequency of crossing over between two loci depends on their distance: closer genes are less likely to be separated.