A genetic marker is a gene or DNA sequence with a renowned position on a chromosome that can be utilised to recognise individuals or species. It can be described as a variety (which may originate due to mutation or alteration in the genomic loci) that can be discerned. A genetic marker may be a short DNA sequence, such as a sequence surrounding a lone base-pair change (lone nucleotide polymorphism, SNP) or a long one, like minisatellites. Genetic markers can be used to study the connection between an inherited disease and its genetic causes (for demonstration, a specific mutation of a gene that outcomes in a defective protein). It is known that parts of DNA that lie near each other on a chromosome are inclined to be inherited together. Genetic markers are engaged in genealogical DNA checking for genetic genealogy to determine genetic distance between persons or populations. Uniparental markers (on mitochondrial or Y chromosomal DNA) are revised for considering maternal or paternal lineages. Autosomal markers are utilized for all ancestry. Genetic markers have to be easily identifiable, affiliated with a specific locus and highly polymorphic because homozygote’s do not supply any information. Detection of the marker can be directed by RNA sequencing, or indirect utilizing allonyms.