The human genome contains many submicroscopic copy number variations which includes deletions, duplications and insertions. Although conventional karyotyping remains an important diagnostic tool in evaluating a dysmorphic patient with mental retardation, molecular diagnostic technology such as array comparative genomic hybridization (aCGH) has proven to be sensitive and reliable in detecting these submicroscopic anomalies. A 3 month-old infant with dysmorphic facies, microcephaly and global developmental delay was referred for genetic evaluation. Preliminary karyotyping which was confounded by the quality of metaphase spread was normal; however, aCGH detected a 30.6Mb deletion from 5p15.33-p13.3. This case illustrates the usefulness of aCGH as an adjunctive investigative tool for detecting chromosomal imbalances.

Sequence and phylogenetic analyses of the N, P, M, F, G and L open-reading frames of a Nipah virus isolated from a Pteropus vampyrus illustrated the uniqueness of the genetic signature of this virus compared to all the other Malaysian isolates of Nipah virus from pigs, bat (Pteropus hypomelanus) and humans, as well as the Nipah virus isolated from Pteropus lylei in Cambodia, and that from human in Bangladesh. The Nipah virus of P. vampyrus is more closely related to the Nipah virus isolate from P. lylei, Cambodia than to Nipah virus human isolate of Bangladesh.