Distal 3p deletion syndrome leads to a highly variable phenotype, as almost all chromosomal aberrations do. Although, unlike most chromosomal rearrangements (which invariably correlate with psychomotor retardation), some patients with 3p deletion are phenotypically normal and do not have psychomotor retardation. Indeed, Cuoco C et al recently confirmed the reduced penetrance of distal deletions of 3p: they found the identical distal 3p26.3 deletion in two affected siblings, but also in the unaffected father (PMID: 21457564). Gunnarsson C et al also demonstrated that the typical phenotype generated by distal 3p deletion can be also caused by interstitial 3p deletions (PMID: 21082655). However, we could retrive no data on whether also the interstitial deletion may be asymptomatic. Tutulan-Cunita AC, recently published a review on all known cases of 3p interstitail deletion syndrome (PMID: 22290856).
References: see text.
