A haplotype is a set of genes located side by side on a chromosome. They are generally transmitted together to the next generation and are called "genetically linked".
The chromosome recombination process during meiosis may interrupt the group of genes, which are then separated onto two different homologous chromosomes. However, the likelihood of a crossing-over event within this group of genes is low. The "distance" separating two genes is proportional to the likelihood of two genes being separated in the next generations and is expressed in centimorgans (cM).
A group of genes located close to each other is a haplotype. © DR