The genetic diseases that exhibit a criss-cross pattern of inheritance are primarily linked to X-linked recessive traits. This means that these traits can be passed from mothers to sons and daughters, resulting in a characteristic pattern of inheritance.
Correct Answer
The correct option is A. Haemophilia and colour blindness. Both of these conditions are X-linked recessive disorders, which means they can be inherited in a criss-cross manner.
Explanation of Options
- Haemophilia: A bleeding disorder that is often passed from carrier mothers to affected sons.
- Colour Blindness: A condition affecting the ability to see colors, also inherited from carrier mothers to sons.
- Hypertrichosis of Ear: This condition is not typically associated with criss-cross inheritance.
- Albinism and Sickle Cell Anaemia: These are not X-linked and do not show a criss-cross pattern.
- Klinefelter's Syndrome and Turner’s Syndrome: These are chromosomal disorders, not inherited in a criss-cross manner.
In summary, haemophilia and colour blindness are the only options that demonstrate this unique inheritance pattern.
