imprinting in human disease

One of the best examples of imprinting in human disease is
shown by deletions in the q11-13 region of chromosome 15,
which may cause either Prader–Willi syndrome or Angelman
syndrome. The features of Prader–Willi syndrome are severe
neonatal hypotonia and failure to thrive with later onset of
obesity, behaviour problems, mental retardation, characteristic
facial appearance, small hands and feet and hypogonadism.
Angelman syndrome is quite distinct and is associated with
severe mental retardation, microcephaly, ataxia, epilipsy and
absent speech.