Three articles have been published recently: the complete sequence of two species of turtle to get insight on the evolution of their peculiar body structure, the complete genome sequence of the only known exemplar of white gorilla; a large sequencing and genome wide association study to identify the cause of albinism in white tigers.
The first study appeared at the end of April on Nature Genetics (The draft genomes of soft-shell turtle and green sea turtle yield insights into the development and evolution of the turtle-specific body plan. Wang et al.) describe the complete genome assembly of two kind of turtles (P. sinensis and C. mydas) and also reports interesting results from embryo studies and comparative developmental studies against chicken embryos. Taken together these data give a comprehensive picture on turtle evolution and new insight on the crucial factor driving their peculiar body structure. From extensive analysis of embryo gene expression and comparison with chicken, authors found that turtle development initially follows the common vertebrate pattern but then it differentiate from the stage TK11 and they were also able to identify a set of 233 genes that should be crucial for the specific turtle body plan.
"Taken together, these results suggest that turtles indeed conform to the developmental hourglass model (Supplementary Fig. 15) by first establishing an ancient vertebrate body plan and by developing turtle-specific characteristics thereafter. The above results suggest that turtle-specific global repatterning of gene regulation begins after TK11 or the phylotypic period. Although turtle and chicken express many shared developmental genes in the embryo during the putative phylotypic period (Fig. 4a and Supplementary Tables 27and 28) and have the fewest expanded or contracted gene family members expressed (Supplementary Fig. 16) at this stage, later stages showed increasing differences in their molecular patterns. We found 233 genes that showed turtle-specific increasing expression patterns after the phylotype (Fig. 4b). Considering that the chicken orthologs did not show this type of increasing expression (Supplementary Figs. 17 and 18), these 233 genes represent attractive candidates for clarifying the genomic nature of turtle-specific morphological oddities"
The other two paper deals with some more "exotic" species, trying to dissect the molecular origin of albinism in a white gorilla known as Snowflake and in a family of white tigers raised in captivity. Oculocutaneous albinism in humans is knwon to be related to mutations in the SLC45A2 gene and the authors found that this is the case also in the two considered species.