:: Puzzling Question ::
The offspring from pairing a recessive white male with red eyes with a recessive white hen with red eyes will exhibit which of the following traits:
- (a) 100% recessive white the RED eyes
- (b) 100% recessive white with normal eyes
- (c) 50% recessive white with RED eyes and 50% recessive white with normal eyes
- (d) All of the above
The correct answer is (d) All of the above.
:: Discussion ::
Red eyes are produced by two different factors.
1. SATINET, a recessive sex link factor and
2. INO, a somatic recessive factor
(a.) To obtain 100% recessive whites with red eyes, you would pair a recessive white male with red eyes with a recessive white hen with red eyes. Both members of the pair are either SATINET or both INO.
(b) To obtain recessive white with normal (black) eyes, pair a recessive white male with red eyes (INO) with a recessive white hen with red eyes (SATINET). The male has the trait from a somatic chromosome while the female has the trait from a recessive SEX LINK chromosome. They are not homologous and not in the same chromosome so they cannot exhibit red eyes. They will have BLACK EYES.
100% of the offspring will be carriers of the INO factor. The males will also be split to SATINET.
(c) If you pair a recessive white SATINET male to a recessive white INO hen, as the SATINET is a recessive sex link trait and the INO is a somatic trait, all females will inherit the SATINET trait in the X chromosome. The females will exhibit red eyes and the males will be SATINET carriers with black eyes. 100% of offspring (males and females) will carry the INO trait.