Indeed, homoploid speciation (hybrid speciation without a change in chromosome number) has been evidenced for some fungal species (such as the basidiomycota Microbotryum violaceum). As for plants and animals, fungal hybrids and polyploids display structural and functional modifications compared to their progenitors and diploid counterparts. In particular, the structural and functional outcomes of polyploid Saccharomyces genomes strikingly reflect the evolutionary fate of plant polyploid ones. Large chromosomal rearrangements leading to chimeric chromosomes have been described, as well as more punctual genetic modifications such as gene loss. The homoealleles of the allotetraploid yeast S. pastorianus show unequal contribution to the transcriptome. Phenotypic diversification is also observed following polyploidization and/or hybridization in fungi, producing the fuel for natural selection and subsequent adaptation and speciation. Chromalveolata
Other eukaryotic taxa have experienced one or more polyploidization events during their evolutionary history (see Albertin and Marullo, 2012 for review). The oomycetes, which are non-true fungi members, contain several examples of paleopolyploid and polyploid species, such as within the genus Phytophthora. Some species of brown algae (Fucales, Laminariales and diatoms) contain apparent polyploid genomes. In the Alveolata group, the remarkable species Paramecium tetraurelia underwent three successive rounds of whole-genome duplication and established itself as a major model for paleopolyploid studies. Bacteria
Each Deinococcus radiodurans bacterium contains 4-8 copies of its chromosome. Exposure of D. radiodurans to X-ray irradiation or desiccation can shatter its genomes into hundred of short random fragments. Nevertheless, D. radiodurans is highly resistant to such exposures.
Diagnosis
Diagnosis for pigment dispersion syndrome is made with characteristic slit lamp and gonioscopy findings. Management
There is no cure, but pigmentary glaucoma can be managed with eye drops or treated with simple surgeries. If caught early and monitored, chances of glaucoma are greatly reduced. A 2016 Cochrane Review sought to determine the effectiveness of YAG laser iridotomy versus no laser iridotomy for pigment dispersion syndrome and pigmentary glaucoma, in 195 participants, across five studies. No clear benefits in preventing loss of visual field were found for eyes treated with peripheral laser iridotomy. There was weak evidence suggesting that laser iridotomy could be more effective in lowering intraocular pressure in eyes versus no treatment. References


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