Question

22. A Dugger type family (family with 20 kids) has two thirds of their boys suffering from muscu-lar dystrophy. One third of the boys were sporadic and not necessarily genetic. One of the chil-dren gets married and has a son with muscular dystrophy; they would like to have more children, but are worried about the risk of having another affected son, especially after the woman's family is so afflicted. As a geneticist you need to determine whether this is a familial or a sporadic case? Outline an experimental strategy (there may be more than one method available). Don't worry about controls here, just explain the method you would use and how will it give you your answer. (Hint: you know the sequence of the gene and that it is on the X-Chromosome). Your answer also has to be feasible; sequencing the entire chromosome is not a feasible experiment. (10 Points)

Answer 1

The method that can be used to determine the type of disease is by pedigree charts.

These are the charts that are used to show the family history of disease showing the phenotypes and genotypes of the member of a family.

So the use of pedigree to show the occurence of the disease in the family would help in identifying, if the disease can be tranferred to the future generations. This will also help determine, if the disease is dominant or recessive and whether it is more prevalent in males because of it being linked to the X chromosome.

So a pedigree analysis can be a helpful tool.