Parents who do not have Tay-Sachs disease?!
Question: (a recessive disease that causes fats to build up in brain cells of infants causing mental retardation) produce a child who has Tay-Sachs disease. What are the chances that each child born to this couple will have Tay-Sachs? Draw a Punnett square to show why.
Answers: (a recessive disease that causes fats to build up in brain cells of infants causing mental retardation) produce a child who has Tay-Sachs disease. What are the chances that each child born to this couple will have Tay-Sachs? Draw a Punnett square to show why.
Why are people so blatant about wanting someone else to do their homework?
In any case, tay sach's is autosomal recessive. Both parents having the gene is very unlikely, especially compared to the more common genetic disorders (like CF) but it does happen, especially with populations like ashkenazi jews who practice endogamy.
If both the parents ARE carriers for the gene, they have a 1/4 chance of having an unaffected child who does not have symptoms nor carries the gene, a 2/4 chance of having a child who carries the gene but is not symptomatic, and a 1/4 chance of having a child who both carries the gene and is symptomatic.
http://upload.wikimedia.org/wikipedia/co...
