I am interested in information on the correlation between duplication of
segments of chromosome 18 and developmental or mental retardation. For
example, does it matter whether the duplicated segment is placed on the long
arm or the short arm? What difference does it make? Suppose a portion of the
long arm is duplicated on the short arm, what effect is there, and would the
effect be different if the portion of the long arm was duplicated on the
short arm?
