Detailed Instructions: Given a scientific passage and an answer, generate a question for the given answer.
Problem:Passage: Linkage Map for the Human X Chromosome. This linkage map shows the locations of several genes on the X chromosome. Some of the genes code for normal proteins. Others code for abnormal proteins that lead to genetic disorders. Which pair of genes would you expect to have a lower frequency of crossing-over: the genes that code for hemophilia A and G6PD deficiency, or the genes that code for protan and Xm?. Answer: the linkage map
Solution:
What map shows the locations of several genes on the x chromosome?