There isn't one single chromosome definitively "defective" in all types of albinism. The provided text mentions a specific type of albinism (OA), where the gene is located on the X chromosome. However, it's crucial to understand that albinism encompasses several different genetic conditions.
Understanding the Genetics of Albinism
Albinism is not caused by a defect on a single chromosome universally. Different types of albinism are caused by mutations in different genes located on various chromosomes. The provided reference mentions oculocutaneous albinism (OA), where the gene responsible is located on the X chromosome, illustrating a specific example of X-linked inheritance. This means that in this particular type of albinism, the defective gene is on the X chromosome.
-
X-linked inheritance: This pattern, as the reference explains, means the gene is located on the X chromosome. Females have two X chromosomes, and males have one X and one Y. This impacts how the condition is inherited within families.
-
Autosomal Recessive Inheritance: The reference also mentions autosomal recessive inheritance as another pattern of inheritance for albinism. This means the defective gene is on one of the autosomal chromosomes (chromosomes 1-22, not sex chromosomes). Two copies of the mutated gene are required to display the phenotype (the observable characteristic of albinism).
Therefore, the answer depends on the specific type of albinism. The provided reference only describes one type, illustrating the X chromosome involvement. Other types may involve autosomal chromosomes.
