What is the probability that the second child will have the disease?

Autosomal recessive inheritance: Two unaffected people who each carry one copy of the altered gene for an autosomal recessive disorder (carriers) have a 25 percent chance with each pregnancy of having a child affected by the disorder.

What is the probability that their first child will have PKU?

There is a 1/4 chance each birth that a child would have the disease.

When two heterozygous parents reproduce what type s of offspring can they produce?

Therefore, the two possible heterozygous combinations produce offspring that are genotypically and phenotypically identical despite their dominant and recessive alleles deriving from different parents.

What is the probability that a child of theirs will be a carrier of the PKU allele?

Conversely, there also is a 25\% chance that the carrier parents will both pass along the mutated gene, causing the child to have PKU. However, there is a 50\% chance that a child will inherit one normal gene from one parent and one abnormal one from the other, making the child a carrier.

What is the percent probability that the first child of this couple will have Huntington’s disease?

Huntington disease (HD) is inherited in an autosomal dominant manner. This means that having a change (mutation) in only one of the 2 copies of the HTT gene is enough to cause the condition. When a person with HD has children, each child has a 50\% (1 in 2) chance to inherit the mutated gene and develop the condition.

What is the genotype for someone with PKU?

An untreated PKU patient with normal intelligence was found to be heterozygous for the IVS12nt1 and R408W mutations(21). This genotype would be expected to have no PAH activity. Therefore, something other than the activity of the PAH enzyme must be affecting the intellectual phenotype in some individuals.

What is the probability that their first female child will have albinism?

X-linked inheritance When a mother is a carrier of an X-linked type of albinism, each of her daughters has a 1 in 2 chance of becoming a carrier. Each of her sons has a 1 in 2 chance of having albinism.

Which term describes the offspring of a first generation cross between parents with different forms of a trait?

Although an individual gene may code for a specific physical trait, that gene can exist in different forms, or alleles. In other cases, each parent provides a different allele of a given gene, and the offspring is referred to as heterozygous (“hetero” meaning “different”) for that allele.

What gene or chromosome is affected by PKU?

Classical PKU is an autosomal recessive disorder, caused by mutations in both alleles of the gene for phenylalanine hydroxylase (PAH), found on chromosome 12.

What is the probability that if they have another child that the child will be heterozygous for CF?

An individual must inherit two non-functioning CF genes – one from each parent – to have CF. If both parents are carriers there is a 1 in 4 (25 percent) chance that both will pass on the non-functioning gene, which would result in a pregnancy affected with cystic fibrosis.