DNA segments are fragments of nucleotide sequences on chromosomes. The distance between these segments is measured by a unit called cM (centimorgans). The DNA segments play a vital role in the inheritance of genetic information.
The DNA segments are made of nucleotides. Each nucleotide is composed of a nucleobase (A, T, G, C), deoxyribose sugar and a phosphate group.
Centimorgan (cM) is a unit to measure genetic linkage. It infers the distance between loci for which the approximate number of intervening crossovers is 0.01 (for a single generation). The tendency of crossover varies with different chromosomal regions. It also depends on whether the crossing-over (in meiosis) takes place in male or female gametes.
Also Refer: Linkage and Recombination
Difference between DNA Segments and Centimorgans
DNA segment is nothing but the nucleotide sequence of DNA.
Centimorgan is a unit that measures the DNA fragment.
It is responsible for the inheritance of genetic information.
It is a measuring unit to infer genetic linkage.
Frequently Asked Questions on Difference between DNA Segments and Centimorgans
What is a chromosome?
It is a long DNA molecule that is composed of an organism’s genetic material. The DNA molecule is associated with proteins and is termed chromatin. Histone is the basic packaging protein responsible for the organisation of the chromosome.
What is a chromosomal crossover?
It is the process of exchanging genetic material between two chromosomes during sexual reproduction. Crossing over usually happens between non-sister chromatids of homologous chromosomes. This results in recombinant chromosomes. This occurs during the pachytene phase of meiosis.
What is genetic linkage?
It is the tendency of close nucleic acid sequences to be inherited together. Genetic linkage happens during the meiosis phase. The sequences that are near to each other are less likely to be separated during the chromosomal crossover. Usually, the genetic linkage is measured using a unit called centimorgan (cM).
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