The relationship between congenital heart defects (CHD) and chromosomal aberration has been well discussed. Payne et al. suggested that CHD may often be frequently due to a singlegene defect.1 It is known that 22q11.2 deletion syndrome is often associated with tetralogy of Fallot (TOF) and aortic arch anomlies.2,3 The relationship between CHD and chromosome 8 aberration has also been reported. Deletions in the distal region of chromosome 8p (del8p) are associated with CHD, typically in the form of atrioventricular septal defect.4,5 San Luis Valley recombinant chromosome 8 syndrome (SLV Rec8), which is characterized by both deletion of the short arm of chromosome 8 (8p23.1–8pter) and duplication of the long arm of chromosome 8 (8q22.1–8qter), is strongly associated with TOF.6–8 Forty-two out of 45 patients with SLV Rec8 exhibited CHD, 17 of them having TOF.8 We now report two Japanese patients with TOF who showed a chromosomal abnormality: inverted duplication of the short arm of chromosome 8 (inv dup 8) within deletion of 8p23.1–8pter.
