We present a novel approach to deal with the problem of reconstructing the duplication history of tandemly repeated genes that are supposed to have arisen from unequal recombination. We first describe the mathematical model of evolution by tandem duplication and introduce duplication histories and duplication trees. We then provide a simple recursive algorithm which determines whether or not a ...

Duplication is thought to be one of the main processes providing a substrate on which the effects of evolution are visible. The mechanisms underlying this chromosomal rearrangement were investigated here in the yeast Saccharomyces cerevisiae. Spontaneous revertants containing a duplication event were selected and analyzed. In addition to the single gene duplication described in a previous study...

Internal symmetry in proteins is likely to be the footprint of evolution by gene duplication and fusion. Like other symmetrical proteins, β-propellers, which are made of 4-10 β-sheet units (blades) circularly arranged around a central tunnel, have probably evolved by duplication and fusion of a rudimentary repetitive unit. However, reproducing the evolution of functional β-propellers by duplica...

purpose: to report a case who had optic disc duplication, a rare congenital disorder characterized by two well-defined discs in one eye. case report: a 19 months-old child presented with unilateral epiphora in the right eye since birthday. the right eye was smaller than the left eye and mild ptosis was apparent. nasolacrimal duct probing was performed under general anesthesia. the examination r...

Females homozygous for the sex-linked dominant, Bar, occasionally give rise to wild-type reversions and to forms with more extreme eye reduction than Bar. This behavior was shown by Sturtevant' to result from unequal crossing-over. The Bar-reverted type was considered to be a deficiency for the Bar gene; while the extreme form, called Ultra-Bar or Double-Bar, was interpreted as a duplication fo...

Receptor-Like Kinase (RLK)/Pelle genes play roles ranging from growth regulation to defense response, and the dramatic expansion of this family has been postulated to be crucial for plant-specific adaptations. Despite this, little is known about the history of or the factors that contributed to the dramatic expansion of this gene family. In this study, we show that expansion coincided with the ...

Receptor-Like Kinase (RLK)/Pelle genes play roles ranging from growth regulation to defense response, and the dramatic expansion of this family has been postulated to be crucial for plant-specific adaptations. Despite this, little is known about the history of or the factors that contributed to the dramatic expansion of this gene family. In this study, we show that expansion coincided with the ...