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The phenotype associated with a recessive gene is only expressed when two copies of the gene are present. For example, if a person has both a recessive allele and a dominant allele for CF, the person does not have CF. The person only has CF if he/she has two copies of the recessive allele.
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∙ 13y ago
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Why can a person have one copy of the CF allele and be perfectly normal?
CF is recessive, and as such, the gene for non-CF is dominant over this gene. The CF gene will only be expressed in the phenotype and as a characteristic if the person has two of the recessive alleles.
Is CF X-linked or incomplete dominance?
Cystic fibrosis (CF) is an autosomal recessive disorder, not an X-linked disorder. It means that both copies of the gene responsible for CF need to be mutated in order to develop the disorder. Incomplete dominance refers to a genetic trait where the heterozygous condition results in an intermediate phenotype, which is not the case for CF.
What is the chance that any child will have the disease if two parent who are carriers of cystic fibrosis?
Let's do a Punnit Square. T T T TT TT t Tt Tt T is normal, and the little "t" is the recessive gene (which is being carried by one parent). Since one parent is recessive, you can see that there's a 50% chance that the offspring will have the recessive gene as well. However, note that without any straight "tt" result, there is a 0% chance that the offspring can express the Tay Sachs disorder.
How do you know if the recessive gene will be the recessive in the offspring?
If the recessive gene is present in both of the parents.
A gene is recessive when?
Most genes have two copies of each gene with dominant gene "trumping" the recessive one. The gene is recessive because it is said not to do much of anything unless paired with another recessive gene, but if paired with a dominant gene, the dominant gene wins.
Is cystic fibrosis dominant or recessive?
Cystic Fibrosis is recessive. If you have one CF gene and one non-CF gene, you will be a carrier but not have CF.
Why can a person have one copy of the CF allele and be perfectly normal?
CF is recessive, and as such, the gene for non-CF is dominant over this gene. The CF gene will only be expressed in the phenotype and as a characteristic if the person has two of the recessive alleles.
Is CF X-linked or incomplete dominance?
Cystic fibrosis (CF) is an autosomal recessive disorder, not an X-linked disorder. It means that both copies of the gene responsible for CF need to be mutated in order to develop the disorder. Incomplete dominance refers to a genetic trait where the heterozygous condition results in an intermediate phenotype, which is not the case for CF.
What is the chance that any child will have the disease if two parent who are carriers of cystic fibrosis?
Let's do a Punnit Square. T T T TT TT t Tt Tt T is normal, and the little "t" is the recessive gene (which is being carried by one parent). Since one parent is recessive, you can see that there's a 50% chance that the offspring will have the recessive gene as well. However, note that without any straight "tt" result, there is a 0% chance that the offspring can express the Tay Sachs disorder.
What would be the genotype of a person with cystic fibrosis?
The genotype of a person with CF is cc. The genotype of a carrier of a CF mutation is Cc.
Genes that are only seen when paired with a recessive gene?
if u have a recessive gene with a recessive gene then u can see the recessive gene but if you have a dominant gene with a recessive gene you can only see the dominant gene hope that helps:)
How do you know if the recessive gene will be the recessive in the offspring?
If the recessive gene is present in both of the parents.
A gene is recessive when?
Most genes have two copies of each gene with dominant gene "trumping" the recessive one. The gene is recessive because it is said not to do much of anything unless paired with another recessive gene, but if paired with a dominant gene, the dominant gene wins.
What does recessive mean as it relates to genes?
Recessive, as in recessive genes, refers to an inherited characteristic or trait that is expressed only when two copies of the gene responsible for it are present.
Is leukemia a recessive gene?
recessive.
What does it mean when a disease is recessive?
You don't have it but have the gene and are a carrier and could pass it on.
How can a child with cystic fibrosis have two parents that do not have cystic fibrosis?
The parents will both have a specific gene defect. If they do there is then a 1 in 4 chance of them having a child with cf. so if you are considering having children you should have a blood test to find out if you are a carrier of the gene causing cf. hope that helps.
