We describe 2 unrelated Bedouin girls who met the criteria for the diagnosis of Kenny-Caffey syndrome. The girls had some unusual features--microcephaly and psychomotor retardation--that distinguish the Kenny-Caffey syndrome profile in Arab children from the classical Kenny-Caffey syndrome phenotype characterized by macrocephaly and normal intelligence. The 2 girls did not harbor the 22q11 microdeletion (the hallmark of the DiGeorge cluster of diseases) that we previously reported in another Bedouin family with the Kenny-Caffey syndrome (Sabry et al. J Med Genet 1998: 35(1): 31-36). This indicates considerable genetic heterogeneity for this syndrome. We also review previously reported 44 Arab/Bedouin patients with the same profile of hypoparathyroidism, short stature, seizures, mental retardation and microcephaly. Our results suggest that these patients represent an Arab variant of Kenny-Caffey syndrome with characteristic microcephaly and psychomotor retardation. We suggest that all patients with Kenny-Caffey syndrome should be investigated for the 22q11 microdeletion. Other possible genetic causes for the Kenny-Caffey syndrome or its Arab variant include chromosome 10p abnormalities.