We describe a child with ATR-16 [alpha-thalassemia (thal)/mental retardation], 
who was referred for genetic evaluation because of minor anomalies and 
developmental delay. Cytogenetic analysis demonstrated a de novo complex 
rearrangement of chromosome 16. Fluorescence in situ hybridization (FISH) 
analysis, using chromosome 16 subtelomeric probes, showed that this patient had 
a deletion of the distal short arm of chromosome 16 that contains the 
alpha-globin genes and a duplication of 16q. Analysis of the alpha-globin locus 
by Southern blot showed a half normal dose of the alpha-globin gene. 
Microsatellite marker studies revealed that the duplicated 16q region was 
maternal in origin. Hematological studies revealed anemia, hypochromia and 
occasional cells with Hb H inclusion bodies. A hematological screening for 
alpha-thal should be considered in patients with mild developmental delay and a 
suggestive phenotype of ATR-16 with microcytic hypochromic anemia and normal 
iron status. The stellate pattern of the iris, a new finding in our patient, may 
contribute to a better clinical delineation of both syndromes, ATR-16 and/or 
duplication of 16qter.