What are the chances of albinism in monozygotic twins?

The chances of monozygotic (identical) twins both being albino are very high, almost 100%, if both parents are carriers of the albino gene. Since identical twins share the same genetic material, if one twin is albino, the other twin will also be albino as long as both parents carry the gene.

Albinism is an autosomal recessive genetic condition, meaning it is carried on chromosomes that are not sex-linked. For a child to inherit albinism, they must receive two copies of the albino gene, one from each parent. If both parents carry the albino gene, each parent has a 50% chance of passing it on to their child. This means that there is a 25% chance that both identical twins will inherit the albino gene and have albinism.

However, it's important to note that while the chances of both monozygotic twins having albinism are very high if both parents are carriers, it is still possible for only one twin to be albino if there is a mutation in one of the genes involved in melanin production that occurs after conception.