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Population outbreaks of the corallivorous crown-of-thorns starfish (COTS), Acanthaster ‘planci’ L., are considered among the most important biological disturbances of tropical coral reefs. A local COTS outbreak, a “primary outbreak”, can lead to so-called “secondary outbreaks” in adjacent coral reefs due to increased larval release and subsequent dispersion. Previous analyses have shown that in the Pacific Ocean, this dispersion may be geographically restricted to certain regions. Guam, an island in the western Pacific region, suffered from several COTS outbreaks in the last 50 years, and in this study we test whether Guam is genetically connected with surrounding regions as a consequence of secondary outbreaks. We used microsatellites to measure gene flow and genetic structure among 14 localities in the Pacific Ocean. Our results show substantial genetic structure between geographical regions. There was, however, a lack of significant genetic differentiation between localities separated by large geographic distances (e.g., Guam, Kingman Reef and Johnston Atoll) – a finding consistent with the existence of contemporary long distance larval dispersion and the gradual erasing of ancestral signatures of divergence. Long distance larval dispersion suggests that secondary outbreaks occur across regions in the Pacific, and have occurred in the recent outbreaks in Guam. However, significant genetic differences among outbreak localities around the island of Guam were also detected, revealing the signature of both primary and secondary outbreaks. Our findings highlight the importance of addressing likely triggers of both primary and secondary outbreaks in conservation efforts and programs that strive to control the growth and spread of A. ‘planci’ in the Pacific Ocean.

The Chagos Archipelago was designated a no-take marine protected area (MPA) in 2010; it covers 550 000km2, with more than 60 000km2 shallow limestone platform and reefs. This has doubled the global cover of such MPAs. It contains 25-50% of the Indian Ocean reef area remaining in excellent condition, as well as the world's largest contiguous undamaged reef area. It has suffered from warming episodes, but after the most severe mortality event of 1998, coral cover was restored after 10years. Coral reef fishes are orders of magnitude more abundant than in other Indian Ocean locations, regardless of whether the latter are fished or protected. Coral diseases are extremely low, and no invasive marine species are known. Genetically, Chagos marine species are part of the Western Indian Ocean, and Chagos serves as a 'stepping-stone' in the ocean. The no-take MPA extends to the 200nm boundary, and. includes 86 unfished seamounts and 243 deep knolls as well as encompassing important pelagic species. On the larger islands, native plants, coconut crabs, bird and turtle colonies were largely destroyed in plantation times, but several smaller islands are in relatively undamaged state. There are now 10 'important bird areas', coconut crab density is high and numbers of green and hawksbill turtles are recovering. Diego Garcia atoll contains a military facility; this atoll contains one Ramsar site and several 'strict nature reserves'. Pollutant monitoring shows it to be the least polluted inhabited atoll in the world. Today, strict environmental regulations are enforced. Shoreline erosion is significant in many places. Its economic cost in the inhabited part of Diego Garcia is very high, but all islands are vulnerable. Chagos is ideally situated for several monitoring programmes, and use is increasingly being made of the archipelago for this purpose. © 2012 John Wiley and Sons, Ltd.

MPS VII mice are deficient in beta-glucuronidase and share many clinical, biochemical, and pathologic characteristics with human mucopolysaccharidosis type VII (MPS VII). We have shown that syngeneic bone marrow transplantation (BMT) prolongs survival and reduces lysosomal storage in many organs of the MPS VII mouse. In this report, we quantify the hearing loss and determine the impact of syngeneic BMT on the development of deafness and the associated pathology in the MPS VII mouse. Eleven weeks after syngeneic BMT performed at birth, treated MPS VII mice had normal auditory-evoked brainstem responses (ABR), whereas untreated MPS VII mice had ABR thresholds 43 dB higher than normal. Treated MPS VII mice had beta-glucuronidase-positive cells in the temporal bone and in the subepithelial connective tissue of the external auditory canal. There was less thickening of the tympanic membrane and middle ear mucosa and decreased distortion of the ossicles and the cochlear bone. Although transplanted MPS VII mice had increased ABR thresholds by 33 weeks of age, four of the six had thresholds 12 to 32 dB lower than untreated mutants. These data indicate that syngeneic BMT in newborn MPS VII mice prevents early hearing loss and, in some animals, results in long-term improved auditory function.

Bone marrow transplantation (BMT) proved an effective therapy for murine mucopolysaccharidosis type VII (MPS VII) in adult gusmps/gusmps mice with well developed clinical and pathologic characteristics of the disease. MPS VII mice transplanted as adults had a marked decrease in lysosomal storage material in many organs, although not in the skeleton and brain (1). Since untreated newborn MPS VII mice appear normal and have minimal lysosomal storage material detectable microscopically, we postulated that BMT in newborn mice might prevent the subsequent accumulation of storage material.One-day-old mutant and phenotypically normal mice were exposed to 2, 4, 6 and 8 Gray and then injected intravenously with syngeneic bone marrow cells from homozygous normal females. Transplanted mice were examined biochemically and microscopically at 10 weeks and 10 months of age.Newborn mice receiving BMT lived longer than untreated mutants, had less severe facial dysmorphism, and better mobility. beta-Glucuronidase activity in liver, spleen, kidney and brain increased with increasing radiation dose. The secondary elevations of alpha-galactosidase and beta-hexosaminidase observed in MPS VII, were significantly reduced in liver and spleen in all radiation groups. Treated mutants had less histologic evidence of lysosomal storage disease in bones, joints and periarticular tissue as compared with untreated mutants. Neonatal BMT also reduced storage in the leptomeninges, ependyma and retinal pigment epithelium and caused a slight decrease in neuronal storage at high radiation dose. Radiation dose dependent cerebellar and retinal dysplasia and long bone growth retardation was observed when the therapy was initiated in newborn mice but not when the animals were transplanted as adults.BMT is a more effective therapy for MPS VII when it is performed at birth rather than in adults. Alternate means of ablating host hematopoietic stem cells should be employed as a pretreatment for BMT due to the severe side effects of radiation on newborns.