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A couple who are both carriers of the gene for cystic fibrosis have two children who have cystic fibrosis What is the probability that their next child will be phenotypically normal?
Wiki User
∙ 14y ago
If both parents are carriers on cystic fibrosis, just because two children may have the disease it doesn't mean that say,a further 3 children in future will be "normal". Inheriting genes is like a lottery. I can say though that because cystic fibrosis is recessive, every offspring born under carriers will always have a 75% chance of being phenotypically normal.
Wiki User
∙ 14y ago
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What is the probability of two healthy people where one is a carrier being parents to a child born with cystic fibrosis?
If only one person is a carrier of cystic fibrosis than there is no chance of having a child with it. Both parents have to be carriers and even then there is only a 25% chance. If only one carries than there is a 50% chance that their children will carry but will not have cystic fibrosis.
Is it possible for a mother to have two kids with different father be born with cystic fibrosis?
Depends. If your mother has cystic fibrosis and your father is a carrier, there is a 50% chance that any of their children will have cystic fibrosis. If the father is not a carrier, no children will have cystic fibrosis, but they will all be carriers.
What is the probability of a child having cystic fibrosis if one of her parents was homozygous dominant and the other was a carrier for cystic fibrosis?
Assuming that each parent is a carrier for cystic fibrosis (has the genotype Ff), the probability that their second child will develop cystic fibrosis is one fourth. The probability doesn't change with the number of children they have. For each pregnancy, the chance that the child will have cystic fibrosis (have the genotype ff) is exactly the same.
Why does a person with Cystic Fibrosis have the genotype cc?
Cystic Fibrosis is inherited as a recessive trait. This means that both parents have to carry the allele for the defect. Both parents are Cc which means that 25% of their children will be CC (homozyous dominant and will not be able to pass the recessive allele in subsequent generations, 50% will be Cc(carriers) and 25% will be cc (homozygous reccessive and have Cystic Fibrosis).
To be a cystic fibrosis carrier do your parents have to have a cystics fibrosis gene?
Yes, since the disease is a recessive inherted trait BOTH parents must carry the gene but will not have the disease itself. Approximately 30,000 people in the United States have cystic fibrosis. An additional ten million more-or about one in every 31 Americans-are carriers of the defective CF gene, but do not have the disease. The disease is most common in Caucasians, but it can affect all races.
What is the genotype of an individual that is not affected with cystic fibrosis?
Let's call the gene "C." Capital C means no cystic fibrosis; lower c means cystic fibrosis, since it is a recessive gene. CC is a person who does not have cystic fibrosis and also is not a carrier. Cc indicated a carrier. cc shows a person with cystic fibrosis. In order for a child to have cystic fibrosis, its parents must be: 1. cc and cc (both have cystic fibrosis, so every child will as well.) 2. Cc and Cc (both carriers; 25% chance of having a child with cystic fibrosis) 3. Cc and cc (one parent is a carrier and one has cystic fibrosis; there is a 50% chance that the children will have cystic fibrosis.)
How disorder is inherited cystic fibrosis?
Cystic Fibrosis, is a recessive disease (meaning that both parents must be carriers of the cystic fibrosis gene, for the offspring to have a chance of being born with it). A child has a 25% chance (1/4) of being born with Cystic Fibrosis.
Why do inherited diseases like hemophilia and cystic fibrosis occur?
They are caused by the genes that we inherit from our parents. Genes govern how our body is run. Cystic fibrosis is caused by a recessive alle. This means that both parents must be carriers of the alle responsible for cystic fibrosis. The parents don't have to have the condition themselves; they can be just carriers of the one alle that makes up the condition.
Does Cystic Fibrosis affect kids?
yes, everyone who has cystic fibrosis has had it from birth therefore they have it when they are children.
How can one child be born healthly and second one have cystic fibrosis?
To have a child with cystic fibrosis both parents must be a carrier or a sufferer. A carrier is a person who has one healthy gene, and one diseased gene, so they dont have cystic fibrosis but they can pass it on to their children. Children inherit one gene from each parent. To get cystic fibrosis a child must get two copies of the 'disease' gene - one from each parent. If two carriers have children, each child has a 25% chance not getting a Cystic fibrosis disease gene, 50% of being a carrier and 25% of being a sufferer. This is not affected by if the child is male or female. So essentially the answer is bad luck.
If both parents have cystic fibrosis what is the probability that one child will have it?
It depends weather or not the woman carries the cystic fibrosis alele. If she carries a recessive CF allele, then the chances of her and the man having a child with CF is 1/4 But if she doesn't carry it then the child wont have CF but could carry the disorder as a recessive allele. again, the chances of that are 1/4.
Why can Cystic fibrosis be inherited even if neither parent has the disease?
Cystic Fibrosis is an example of a disease inherited as an autosomal recessive genetic disorder. Both parents of a baby who has Cystic Fibrosis have one abnormal recessive gene and one normal dominant gene and are therefore, Cystic Fibrosis carriers. Carriers are said to be heterozygous because they contain one normal copy of the gene and one abnormal copy. A baby who inherits cystic fibrosis has inherited the abnormal gene from both parents and is therefore said to be homozygous recessive.
