Segmental duplications (also termed 'fenestrations') of the fetal anterior cerebral artery are a relatively rare anomaly. Their occurrence was studied in 200 fetuses at 20-40 wk gestational age. Duplications were found in 21 of the 200 fetuses, i.e. 10.5%. In 2 fetuses, i.e. 1%, the duplications were bilateral. In 1 case, i.e. 0.5%, 2 duplications were found on the left anterior cerebral artery...

Segmental duplications are abundant in the human genome, but their evolutionary history is not well-understood. The mystery surrounding them is due in part to their complex organization; many segmental duplications are mosaic patterns of smaller repeated segments, or duplicons. A two-step model of duplication has been proposed to explain these mosaic patterns. In this model, duplicons are copie...

Relative to genomes of other sequenced organisms, the human genome appears particularly enriched for large, highly homologous segmental duplications (> or =90% sequence identity and > or =10 kbp in length). The molecular basis for this enrichment is unknown. We sought to gain insight into the mechanism of origin, by systematically examining sequence features at the junctions of duplications. We...

Various types of repeat sequences are abundant in genomic sequences, and they are associated with the biological phenomena at distinct levels. In particular, comparative analyses of whole-genome-sized sequence data have revealed that repeat sequences cause segmental duplications, which are a type of chromosomal structural arrangement. In this study, we analyzed the relationships between segment...

The non-recombining Y chromosome is expected to degenerate over evolutionary time, however, gene gain is a common feature of Y chromosomes of mammals and Drosophila. Here, we report that a large palindrome containing interchromosomal segmental duplications is located in the vicinity of the first amplicon detected in the Y chromosome of D. melanogaster. The recent appearance of such amplicons su...

Tandem and segmental duplications significantly contribute to gene family expansion and genome evolution. Genome-wide identification of tandem and segmental genes has been analyzed before in several plant genomes. However, comparative studies in functional bias, expression divergence and their roles in species domestication are still lacking. We have carried out a genome-wide identification and...

The completion of the Human Genome Project has brought the understanding that our genome contains an unexpectedly large proportion of segmental duplications. This poses the challenge of elucidating the consequences of recent duplications on physiology. We have conducted an in-depth study of a subset of segmental duplications on chromosome 16. We focused on PKD1 and ABCC6 duplications because mu...