If both parents are carriers of an autosomal recessive trait, the probability of having an affected child is _____%.

Understand the Problem

The question is asking about the genetic probability of a child being affected by an autosomal recessive trait when both parents are carriers. To solve this, we will apply the principles of Mendelian inheritance, analyzing the potential genotypes of the offspring.

More Information

If both parents carry an autosomal recessive gene, each child has a 25% chance of inheriting the gene from both parents and being affected by the related condition. They also have a 50% chance to be carriers like their parents.

Tips

A common mistake is thinking that if both parents are carriers, the chance of an affected child is higher than 25%; however, it remains 25% for each pregnancy.

Sources

• Autosomal recessive inheritance - Knowledge Hub - genomicseducation.hee.nhs.uk
• Carrier Test for Autosomal Recessive Conditions - Columbia Doctors - columbiadoctors.org
• Autosomal recessive inheritance - MedlinePlus - medlineplus.gov