Two brothers with 22q13 deletion syndrome and features suggestive of the Clark-Baraitser syndrome

We report on two brothers with moderate-to-severe mental retardation, severe macrocephaly, obesity, characteristic face, big hands and feet, advanced bone age and brain abnormalities, including frontal cortical atrophy. These two boys resembled the two brothers described by Clark and Baraitser (1987), two maternal cousins subsequently reported by Baraitser et al. (1995) and a Brazilian boy described by de Pina-Neto and Andreotti-de Molfetta (1998). Upon further investigation, we detected a cryptic subtelomeric deletion of chromosome region 22q13, not present in either parent and probably due to a maternal germinal mosaicism. Thus, we describe the first familial case of 22q13 deletion and recommend that patients with a phenotype suggestive of the so-called Clark-Baraitser syndrome be tested for submicroscopic 22qter deletion.