Albinism is a recessive trait in humans. A geneticist studies a series of families in which both parents are normal and at least one child has albinism. The geneticist reasons that both parents in these families must be heterozygotes and that albinism should appear in ¼ of the children of these families. To his surprise, the geneticist finds that the frequency of albinism among the children of these families is considerably greater than ¼. There is no evidence that normal pigmentation exhibits incomplete penetrance. Can you think of an explanation for the higher-than-expected frequency of albinism among these families?

Albinism is a recessive trait in humans. A geneticist studies a series of families in which both parents are normal and at least one child has albinism. The geneticist reasons that both parents in these families must be heterozygotes and that albinism should appear in ¼ of the children of these families. To his surprise, the geneticist finds that the frequency of albinism among the children of these families is considerably greater than ¼. There is no evidence that normal pigmentation exhibits incomplete penetrance. Can you think of an explanation for the higher-than-expected frequency of albinism among these families?

Name: Albinism is a recessive trait in humans. A geneticist studies a series
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Description: Albinism is a recessive trait in humans. A geneticist studies a series of families in which both parents are normal and at least one child has albinism. The geneticist reasons that both parents in these families must be heterozygotes and that albinis

Human Heredity: Principles and Issues (MindTap Course List)

11th Edition

ISBN:9781305251052

Author:Michael Cummings

Publisher:Michael Cummings

Chapter15: Genomes And Genomics

Section: Chapter Questions

Problem 2QP: Hemophilia and color blindness are both recessive conditions caused by genes on the X chromosome. To...

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Albinism is a recessive trait in humans. A geneticist studies a series of families in which both parents are normal and at least one child has albinism. The geneticist reasons that both parents in these families must be heterozygotes and that albinism should appear in 1/4 of the children of these families. To his surprise, the geneticist finds that the frequency of albinism among the children of these families is considerably greater than 1/4. Can you think of an explanation for the higher than-expected frequency of albinism among these families ?
Albinism is a recessive trait in humans.A geneticist studies a series of families in which both parents have normal pigmentation and at least one child has albinism. The geneticist reasons that both parents in these families must be heterozygotes and that albinism should appear in 14 of their children. To his surprise, the geneticist finds that the frequency of albinism among the children of these families is significantly greater than 14. Can you think of an explanation for the higher-than-expected frequency of albinism among these families?
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Albinism is a recessive trait in humans . A geneticist studies a series of families in which both parents havenormal pigmentation and at least one child has albinism. The geneticist reasons that both parents in these families must be heterozygotes and that albinism should appear in 14 of their children. To his surprise, the geneticist finds that the frequency of albinism among the children of these families is significantly greater than 14. Can you think of an explanation for the higher-than-expected frequency of albinism among these families?
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Albinism is a recessive trait in humans. A geneticist studies families in which both parents are normal and at least one child has albinism. The geneticist reasons that both parents in these families must be heterozygous and the albinism should appear in 1⁄4 of the children of these families. To his surprise, the geneticist finds the frequency of albinism trait is quite high. As a consultant, can you suggest an explanation for the higher expected frequency of albinisms in these families?
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