In the context of genetics, what does the phenotype of an individual with the genotype XhY represent?
A
The genetic makeup of a female carrier of hemophilia
B
The presence of a dominant allele for hemophilia
C
The physical expression of hemophilia in a male
D
The absence of any genetic disorder
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Understand the basics of sex-linked inheritance: Hemophilia is a genetic disorder that is often linked to the X chromosome. In humans, males have one X and one Y chromosome (XY), while females have two X chromosomes (XX).
Identify the genotype given: The genotype XhY indicates a male individual because it includes one X chromosome and one Y chromosome. The 'h' denotes the presence of the hemophilia allele on the X chromosome.
Determine the expression of the genotype: Since males have only one X chromosome, any allele present on it will be expressed in the phenotype. Therefore, the presence of the 'h' allele on the X chromosome means the male will express hemophilia.
Contrast with female carriers: A female carrier of hemophilia would have the genotype XhX, where one X chromosome carries the hemophilia allele and the other does not. She would not express hemophilia but could pass the allele to her offspring.
Conclude the phenotype: The genotype XhY results in the physical expression of hemophilia in a male, as there is no second X chromosome to mask the effect of the hemophilia allele.