One morphological variant of chromosome 1 in man differs from the more usual form of this chromosome in being longer and more submetacentric. This is due to increased length of the long arm and because there is apposition of chromatids in the paracentromeric region of the long arm (q). This variant, or similar appearing variants ofchromosome 1, have been found in 1 per 100 to 1 per 1000 newborn...

The accurate and complete replication of genomic DNA is essential for all life. In eukaryotic cells, the assembly of the multi-enzyme replisomes that perform replication is divided into stages that occur at distinct phases of the cell cycle. Replicative DNA helicases are loaded around origins of DNA replication exclusively during G1 phase. The loaded helicases are then activated during S phase ...

We report a 12-year-old boy referred to the Clinical Genetics service in view of facial dysmorphism, learning difficulties and autistic spectrum disorder. 60K arrayCGH revealed an 8.2-Mb duplication on chromosome 13q31.3q32.3, which was paternally inherited. This specific duplication on chromosome 13 has not been previously reported in the medical literature, and there are no familial or de nov...

Pathogen resistance genes represent some of the most abundant and diverse gene families found within plant genomes. However, evolutionary mechanisms generating resistance gene diversity at the genome level are not well understood. We used the complete Arabidopsis thaliana genome sequence to show that most duplication of individual NBS-LRR sequences occurs at close physical proximity to the pare...

Patients with a duplication from 7q36 to the terminus or a deletion of 9p24 have been reported, whereas those harboring both mutations have not. Here, we report a patient with simultaneous de novo 7q36.1-q36.3 duplication and 9p24.3 deletion. A 6-year-old boy presented with speech developmental delay, microcephaly, and dysmorphic features, including a long face and small nose. Chromosome and ar...

We report a 14-year-old Hispanic male with a microduplication of the chromosome 7p22.2 band detected through microarray analysis. He had a history of developmental delay and mild intellectual disability, asthma, myopia, proportionate short stature, dysmorphic features, and Achilles tendon release. This appears to be the first report of a patient with a microduplication of only the chromosome 7p...

The Drosophila melanogaster genome contains a single region (at 83DE on the polytene chromosome map) for which both heterozygous deficiency and heterozygous duplication are inviable. Seven EMS-induced mutations have been recovered that are viable in combination with a duplication of this region. Two classes of mutations are reported: (1) Mutations that allow survival of flies with either a dupl...