Final answer:
For Mendelian traits, both parametric linkage analysis and examining chromosomal rearrangements are used to locate disease genes. These techniques are effective for single-gene disorders with simple inheritance patterns.
Step-by-step explanation:
To find the disease gene for a Mendelian trait, parametric linkage analysis and examining chromosomal rearrangements would typically be used. These methods are well-suited to investigate traits that follow Mendel's laws of inheritance, which are caused by single genes and have clear patterns of segregation in families.
Parametric linkage analysis is a method that involves looking for co-segregation of traits within families. Researchers track the inheritance of known genetic markers and the disease phenotype through the pedigree to calculate the likelihood that certain genes are linked to the disease. In cases where the causative gene is located near a genetic marker, the disease trait and the marker will be inherited together more frequently than would be expected by chance.
Examining chromosomal rearrangements can also help identify disease genes for Mendelian traits. Techniques like karyotyping or fluorescent in situ hybridization (FISH) can visually reveal large scale chromosomal alterations such as deletions, duplications, inversions, or translocations that might be implicated in a disease.
So, the answer to the student's question would be E (Both A and C).