For example, a recent (2007) study by Sebat et al. found a clear link between ASD and de novo copy number variation (de novo mutations are those that arise for the first time in the children).

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Universal grammar allows for variation along a certain number of parameters, and this explains the grammatical variation we observe in natural language.

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The result is variation in the number of copies of that sequence, a variability we call CNV.

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The researchers found that by just analysing sunlight, they could explain 61% of the variation in the number of MS cases across England.

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The elegant basic idea is that variation along a small number of universal dimensions of emotion and cognition can account for the entire stunning range of human morality.

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The magnitude of the variation is measurable and is affected by the number of interviews and the level of the percentages expressing the results.

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But if we recognize that we have such a big variation in Australia, and on average quite a high number, then it is reason enough to have a closer look at what the same assessment would tell us for the other continents.

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The lab number is just an estimate, it's subject to some normal variation and it naturally declines with age.

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Of course the number of people actually born in each month also varies, but this does not explain the variation in Oxbridge admissions.

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But since some variation is permitted at most positions within a binding site, it means that the total number of different possible versions of a site is often large.

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