RT Journal Article SR Electronic T1 Triple structural mosaicism of chromosome 18 in a child with MR/MCA syndrome and abnormal skin pigmentation. JF Journal of Medical Genetics JO J Med Genet FD BMJ Publishing Group Ltd SP 614 OP 615 DO 10.1136/jmg.30.7.614 VO 30 IS 7 A1 E Bocian A1 T Mazurczak A1 E Buława A1 H Stańczak A1 G Rowicka YR 1993 UL http://jmg.bmj.com/content/30/7/614.abstract AB A case of triple mosaicism involving chromosome 18 is described in a girl with abnormal skin pigmentation similar to hypomelanosis of Ito. The karyotype is 46,XX, -18, + del(18)(p11.23-->pter)/46,XX, -18, + idic(18)(p11.23)/46,XX, -18, + r(18). The patient displays some clinical features of monosomy 18p and a few signs of trisomy 18q. Our case illustrates a non-random association of chromosomal mosaicism with abnormal skin pigmentation.