1.19 Questionable suitability of OECD 237 protocol in risk assessment scheme?

Persistent xenobiotics are potentially hazardous for the bee larvae despite that they are not directly exposed in contrary to adult foraging bees. The crucial phase of larval development is the first six days after hatching when young larva grows exponentially and during this phase larvae are potentially exposed to xenobiotics via diet. That is why the life cycle of honeybee is still a great challenge for scientists. OECD reflected “this need” and adopted the OECD 237 protocol (Honey bee (Apis mellifera) larval toxicity test, single exposure) on 26th July 2013. The protocol addresses the requirements formulated by the United States, Canada, and Europe to test the toxicity of chemicals compounds on larvae fed with spiked food under laboratory conditions in a tier1 strategy.Persistent xenobiotics are potentially hazardous for the bee larvae despite that they are not directly exposed in contrary to adult foraging bees. The crucial phase of larval development is the first six days after hatching when young larva grows exponentially and during this phase larvae are potentially exposed to xenobiotics via diet. That is why the life cycle of honeybee is still a great challenge for scientists. OECD reflected “this need” and adopted the OECD 237 protocol (Honey bee (Apis mellifera) larval toxicity test, single exposure) on 26th July 2013. The protocol addresses the requirements formulated by the United States, Canada, and Europe to test the toxicity of chemicals compounds on larvae fed with spiked food under laboratory conditions in a tier1 strategy

Novel <b><i>VANGL1</i></b> Gene Mutations in 144 Slovakian, Romanian and German Patients with Neural Tube Defects

Neural tube defects (NTDs) are a group of congenital malformations of the central nervous system occurring at an average rate of 1 per 1,000 human pregnancies worldwide. Numerous genetic and environmental factors are discussed to be relevant in their etiology. In mice, mutants in &gt;200 genes including the planar cell polarity (PCP) pathway are known to cause NTDs, and recently, heterozygous mutations in the human &lt;i&gt;VANGL1&lt;/i&gt; gene have been described in a small subset of patients with NTDs. We performed a &lt;i&gt;VANGL1&lt;/i&gt; mutation analysis in 144 unrelated individuals with NTDs from Slovakia, Romania and Germany and identified 3 heterozygous missense mutations: c.613G&gt;A (p.Gly205Arg) with an open spina bifida (lumbosacral meningomyelocele), c.557G&gt;A (p.Arg186His) with a closed spina bifida (tethered cord and spinal lipoma) and c.518G&gt;A (p.Arg173His) with an unknown NTD. The c.613G&gt;A mutation was also found in a healthy sibling. None of the mutations were described previously. Findings support that heterozygous &lt;i&gt;VANGL1&lt;/i&gt; mutations represent hypomorphs or conditional mutants predisposing to NTDs and occur at a frequency of approximately 2.1% of open and closed spinal NTDs. The mutations (p.Arg173His, p.Arg186His, p.Gly205Arg) modified conserved regions of the VANGL1 protein and shared similarities with previously described mutants, providing further evidence for the presence of mutational hot spots in these patients.</jats:p