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Found Allele 55 times.

Displaying results 1 to 10.

1. Alleles
Alternative forms of a genetic locus; a single allele for each locus is inherited separately from each parent (e.g., at a locus for eye color the allele might result in blue or brown eyes).

2. Alleles
Alternate forms of a gene .

3. Amorphic allele
An allele which is genetically inactive.

4. Autosomal dominant (autosomal dominance)
This is a type of genetic inheritance ; a person who carries the gene on one allele will express (experience effects from) that gene. An autosomal dominant gene can be inherited from a single affected parent; both sons and daughters have an equal chance of inheriting the gene.

5. Backcross (back cross)
A population created by crossing an individual back to one of its parents. This mating design enables the comparison of the effect of the allele s contributed by one parent against the genetic background of the recurrent parent.

6. Balanced lethal system
A population with non-linked, recessive allele s of a gene , where an individual who has two copies of the recessive allele and is therefore homozygous is dead, while an individual who has only one copy of it, and one copy of a different allele (and is heterozygous ) survives.

7. Balanced polymorphism
A type of polymorphism where the many morphs are allele s. The polymorphism is maintained in a population rather than the norm of one allele eventually becoming the only allele in the population, because individuals who are heterozygous , or have two different alleles, are more adaptive (more "fit") than individuals who are homozygous , or have two copies of the same allele.

8. Balanced stock
A genetic strain of any of several lab organisms (like fruit flies) which can be maintained as heterozygous individuals without requiring constant artificial selection for the heterozygotes, due to a number of lethal recessive gene s with the result that the homozygous females are sterile (unable to produce offspring) and the males with the wrong recessive alleles are dead. (Male fruit flies are not homozygous or heterozygous because they only have one allele per particular genetic loci in question).

9. Barriers to gene flow
Factors, such as geographic, mechanical, and behavioral isolating mechanisms that restrict gene flow between populations , leading to populations with differing allele frequencies.

10. Bobbed
The name for a variety of Drosophila (a fruit fly) mutation where the bristles (mostly on the back of the head) are very short and thin compared to normal fruit fly bristles. Also, the number of copies of gene s encoding rRNA molecules are reduced.The mutant allele is located on the sex chromosome s and is recessive .

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