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Found Homozygous 19 times.

Displaying results 1 to 10.

1. Autosomal recessive
An autosomal recessive gene is one which is required in two copies on an autosome to be active in an organism. For instance, a person who carry two copies of the same abnormal gene (in other words, this person is homozygous for the gene) will experience effects from that gene (for instance, he or she might then suffer from a disease coded by that gene). The gene can be inherit ed from both parents who carry the gene; sons and daughters have an equal chance of inheriting the gene. If a person has a genetic disease but his or her parents seem normal, then this probably means that: * The parents of this person are heterozygous , unaffected carriers of the disease, or * The person inherited one copy of the gene from a parent, and the other "good" copy underwent a mutation early in the person's embryonic development

2. Back cross
A crossing of a heterozygous organism and one of its homozygous parents.

3. 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.

4. 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.

5. 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).

6. Balancing selection
A process of natural selection where heterozygous individuals are more adaptive, and thus selected for more often, than either of the two types of homozygous individuals.

7. Beta thalassemia
This form of thalassemia is due to point mutation s, further subdivided according to pathogenesis: * beta thalassemia major: in this form of beta thalassemia, patients are homozygous for the defective genes: beta0, homozygous beta+, both are life-threatening. * beta thalassemia minor: patients are heterozygous for the defective gene; they have a mild anemia .

8. Fixation
* An attachment. Being affixed. Immobilization by being glued to something solid. * Evolutionarily , a state where every single individual within a population is homozygous for a particular allele (and therefore the phenotype that the allele confers). For example, in a population where everyone has blue eyes, the allele for blue eye color is fixed and everyone will continue to have blue eyes in the future, as long as no new individuals come into the population from elsewhere. * Psychologically, an obsessive amount of attention toward something. * The conversion of an inorganic source of an element (like nitrogen or carbon) into an organically useful form.

9. Genospecies
* A line of homozygous self- fertilizing organisms which perpetuates by inbreeding or cloning . * All genotype s in a species .

10. Hemoglobin S (haemoglobin S)
Hemoglobin S is an abnormal version of the protein hemoglobin . The sixth amino acid of the normal beta chain, glutamic acid , is replaced by valine with gluconic acid . This mutation causes the red blood cell to take on a sickle shape, and is the cause of the sickle cell trait condition (when the individual is heterozygous for this mutant hemoglobin) and the disease of sickle cell anemia (when the individual is homozygous for this mutant hemoglobin).

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