Answer :
A specific heritable point on a chromosomal is called chromosomal fragile site and associated with Fragile X syndrome, consequently Heather has down-syndrome and Gary has Fragile X
Answer;
A. Gary might have DiGeorge syndrome and Heather might have Fragile X syndrome.
Explanation;
-DiGeorge syndrome is a syndrome caused by the deletion of a small segment of chromosome 22. It is characterized by cellular (T-cell) deficiency, characteristic faces, congenital heart disease and hypocalcemia.
-A specific heritable point on a chromosomal is called chromosomal fragile site and is associated with Fragile X syndrome. Fragile X syndrome is a genetic condition that causes intellectual disability, behavioral and learning challenges and various physical characteristics.