pärilikkusemehhanismile, kus meioos ja viljastumine kombineerivad vanemate genoomielemente geneetiliselt erinevatesse sigirakkudesse (gameetidesse või eostesse) ja sügootidesse. Eristatakse interkromosoomset rekombinatsiooni ja intrakromosoomset rekombinatsiooni. Prokarüootidel ja viirustel esineb mitmesuguseid osalise geneetilise rekombinatsiooni protsesse. Balancer Chromosomes are special, modified chromosomes used for genetically screening a population of organisms to select for heterozygotes. Balancer chromosomes can be used as a genetic tool used to prevent crossing over (genetic recombination) between homologous chromosomes during meiosis. Balancers are most often used in Drosophila melanogaster (fruit fly) genetics to allow populations of flies carrying heterozygous mutations to be maintained without constantly screening for the mutations but can also be used in mice.[1] Balancer chromosomes have three important properties: they
comprises the white belly patch, mitts, locket and blaze. In medium grade spotting, the amount of white varies from 40% to 60% of the coat and is the typical pattern of a show quality bicolour (a mask and mantle effect). When it is extensive (more than 60%), it is called high-grade spotting - the Seychellois or Van pattern. Piebald spotting is a semi-dominant gene with very variable expression. Low grade spotted cats and some medium grade, spotted cats are heterozygotes i.e. they have only one copy of the white spotting gene. Other medium grade spotted cats and all high grade spotted cats are homozygotes i.e. they have 2 copies of the gene. Where cats are in the medium spotted range it is generally impossible to know whether they are heterozygotes or homozygotes unless they are bred to a cat known to be either homozygous or heterozygous. To further complicate matters for breeders, some apparently non-piebald cats are really piebald cats whose white
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