In which type of genetic inheritance does a father transmit a trait only to his daughters?

In which type of genetic inheritance does a father transmit a trait only to his daughters?

• A. Autosomal dominant
• B. Autosomal recessive
• C. X-linked dominant
• D. X-linked recessive

Answer: (C)

In X-linked dominant inheritance, a father passes the trait specifically to his daughters because he provides them with one X chromosome, which carries the trait. Males have one X and one Y chromosome, so when they contribute their Y chromosome to sons, those sons do not inherit the X-linked trait. This pattern is characteristic of X-linked dominant traits, where affected males will always have affected daughters, as they pass their single X chromosome to the daughters. Sons, on the other hand, cannot inherit X-linked dominant traits from their fathers, as they receive the Y chromosome instead. In contrast, autosomal dominant and autosomal recessive inheritance would not restrict trait transmission in this way, as these patterns involve both sexes equally without a preference for daughters. X-linked recessive inheritance would also allow for the possibility of affected sons if the mother carries the gene, which is not the case for X-linked dominant traits where an affected father does not pass the trait to his sons.

In X-linked dominant inheritance, a father passes the trait specifically to his daughters because he provides them with one X chromosome, which carries the trait. Males have one X and one Y chromosome, so when they contribute their Y chromosome to sons, those sons do not inherit the X-linked trait.

This pattern is characteristic of X-linked dominant traits, where affected males will always have affected daughters, as they pass their single X chromosome to the daughters. Sons, on the other hand, cannot inherit X-linked dominant traits from their fathers, as they receive the Y chromosome instead.

In contrast, autosomal dominant and autosomal recessive inheritance would not restrict trait transmission in this way, as these patterns involve both sexes equally without a preference for daughters. X-linked recessive inheritance would also allow for the possibility of affected sons if the mother carries the gene, which is not the case for X-linked dominant traits where an affected father does not pass the trait to his sons.