Merozygote

Merozygote is a state when a cell, usually bacterial, is temporarily diploid as result of DNA transfer processes like conjugation.

One example of how merozygotes can be formed is the transfer of genetic material during an HFR transformation. In HFR transformation, an F+ prokaryote transfers its F-factor into an Hfr cell. This F-factor plasmid is incorporated into Hfr DNA. When Hfr mates with an F- cell, the chromosome acts as a rolling circle transferring information across a sex pilus. The F-factor is the last thing on the circle and often isn't transferred to the F- cell, so it remains an F- cell, but has all the extra genetic information from the transferred Hfr chromosome. This temporary partial diploid of the DNA may lead to recombination between the corresponding portions of the DNA, so that the genetic material of the donor may be incorporated into the chromosome of the recipient, thereby altering the genotype of the recipient. However, if no recombination occurs, the linear fragment of donor DNA in the recipient cytoplasm will be lost after one cycle. These merozygotes help to study dominance variation and mutation can be known.