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The following pedigree depicts the inheritance of an X-linked recessive trait.
The phenotype of the progeny 1A, 1B and 1C is unknown. What could be the possibility for the progeny?
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The phenotype of the progeny 1A, 1B and 1C is unknown. What could be the possibility for the progeny?
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Only offspring 1A would be affected.
Pedigree analysis provides information regarding inheritance of particular traits or diseases and using it we can predict the possibility of appearance of any traits in the new generation.
Sex-linked recessive disorders are inherent disorders due to mutation in the sex chromosomes, generally the X chromosome. As per the diagram, the female is homozygous for the recessive trait and shows it phenotypically. Since the son (1A) receives X chromosome from mother and Y chromosome from father, the X-linked trait will get expressed in the son. But it will not be expressed in the daughter as she is receiving only one X-from mother and other X chromosome from father resulting in heterozygous condition.
X-linked recessive traits show phenotypically in females only in homozygous condition.
Sex-linked recessive disorders are inherent disorders due to mutation in the sex chromosomes, generally the X chromosome. As per the diagram, the female is homozygous for the recessive trait and shows it phenotypically. Since the son (1A) receives X chromosome from mother and Y chromosome from father, the X-linked trait will get expressed in the son. But it will not be expressed in the daughter as she is receiving only one X-from mother and other X chromosome from father resulting in heterozygous condition.
X-linked recessive traits show phenotypically in females only in homozygous condition.
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