Galactosemia is an autosomal recessive disorder caused b...

Question

Galactosemia is an autosomal recessive disorder caused by the inability to metabolize galactose, a component of the lactose found in mammalian milk. Galactosemia can be partially managed by eliminating dietary intake of lactose and galactose. Amanda is healthy, as are her parents, but her brother Alonzo has galactosemia. Brice has a similar family history. He and his parents are healthy, but his sister Brianna has galactosemia. Amanda and Brice are planning a family and seek genetic counseling. Based on the information provided, complete the following activities and answer the questions.

Draw a pedigree that includes Amanda, Brice, and their siblings and parents. Identify the genotype of each person, using G and g to represent the dominant and recessive alleles, respectively.

Accepted Answer

Everyone. Let's take a look at this question together. A couple has one child with galactus E MIA and one child without the condition. What is the probability that their next child will have galactose E Mia? So let's recall what we know about galactose anemia and its inheritance pattern to figure out what the probability that their next child will have the condition. So we know that we have one child with galactus E MIA and one child without the condition. And we know that galactus E mia is and inherited disorder, meaning that it is caused bye genetic mutations which are passed down from the parents to the child. And we know that the inheritance pattern of galactose anemia is autism away recessive, Meaning that two copies of the mutated jean are required to express the condition, which means that we're looking for an offspring with the genotype of Homo Saugus recessive. And since the couple has one child with black toxemia and one child without, it is likely that both parents must be carriers for that mutant allele. And so it is likely that the parents are both hetero zegas, Which we know that when we do a cross of two heterosexual parents. We have that 1-1 genotype ratio and that we have that Hamas is dominant. We have the hetero zegas and the Hamas agus excessive where we have a 25% chance of the Hamas is dominant. 50% chance Vegas and 25% chance Hamas, I guess recessive which this homesickness, recessive is the genotype for the child that does express galactus e mia. So that mean that the probability that their next child will have galactose anemia is 25%. Which means that answer choice. A 25% is the correct answer because we know that galactus E mia is an inherited disorder that is caused by genetic mutations which are passed down from parent to child and it is passed down in an autism, a recessive inheritance pattern Which means that we need two copies of the mutated gene in order to express the condition, which genotype where you have two copies of the mutated gene is homogeneous recessive which when we cross the two parents, the probability that their next child will have black toxemia is 25% or answer choice. A I hope you found this video to be helpful. Thank you and goodbye.

Key Concepts

Autosomal Recessive Inheritance

Pedigree Analysis

Genotype Representation

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