Freckles are a dominant trait. Freckles come from genes and the sun and are most often seen on people with light-colored skin.Continue Reading
Freckles are a result of exposure to the ultraviolet light that comes from the sun. Melanin is made when the sun's rays hit the skin as a way of shading and protecting it. If a person produces melanin evenly, it's called tanning. Those people who produce it in clumps tend to freckle.
Scientists are not sure as to why some people tan and others freckle. They suspect it's because the gene that causes freckles, called MC1R, doesn't work well in some people. In those people whose MC1R gene fails on two levels, red hair and freckles are prominent traits. It is more common for the gene to fail on the level that causes freckles than it is to fail and produce both red hair and freckles.Learn more about Molecular Biology & DNA
A multiple allele trait is one of at least three different types of a specific gene, but only two of these types are able to exist in a diploid. A diploid is a type of organism or cell that has two sets of chromosomes, with one set typically from the father and the other from the mother.Full Answer >
Recombinant DNA techniques allow certain genes to be directly transplanted from one organism into distantly related species, which has the effect of imbuing the recipient organism with a new trait such as resistance to cold weather or the ability to produce insulin, according to Rensselaer Polytechnic. Possible drawbacks include the unintended release of modified organisms and the sometimes unpredictable results of direct gene insertion.Full Answer >
A homozygote is an individual organism with two copies of the same allele that determines a specific trait, while a heterozygote has a copy of two different alleles for the same trait. Alleles are alternative forms of genes that determine the same trait.Full Answer >
The father does not carry the gene for non-identical twins, as releasing more than one egg at a time is a trait that runs in the maternal line. There is no evidence suggesting that identical twins run in families. Women who experience a multiple pregnancy are at higher risk of certain complications.Full Answer >