With Reference to Imprinting Disorders, Which, If Any, of the Following

Multiple Choice

With reference to imprinting disorders, which, if any, of the following statements is false?

A) About one quarter of individuals with Angelman syndrome lack a paternal chromosome 15.
B) With the exception of abnormal chromosome segregation, imprinting disorders always result from a deletion or inactivating mutation within, or spanning the imprinted gene cluster.
C) In some imprinting disorders, disease results from inappropriate biallelic expression of a gene.
D) Angelman and Prader-Willi syndrome are very different disorders but can be caused by precisely the same large deletion at 15q11-q13.