Institute of Computational Biology, Helmholtz Zentrum Muenchen, German Research Center for Environmental Health, Neuherberg, Germany.
Environ Health. 2013 Aug 15;12:63. doi: 10.1186/1476-069X-12-63.
The ratio of male to female offspring at birth may be a simple and non-invasive way to monitor the reproductive health of a population. Except in societies where selective abortion skews the sex ratio, approximately 105 boys are born for every 100 girls. Generally, the human sex ratio at birth is remarkably constant in large populations. After the Chernobyl nuclear power plant accident in April 1986, a long lasting significant elevation in the sex ratio has been found in Russia, i.e. more boys or fewer girls compared to expectation were born. Recently, also for Cuba an escalated sex ratio from 1987 onward has been documented and discussed in the scientific literature.
By the end of the eighties of the last century in Cuba as much as about 60% of the food imports were provided by the former Soviet Union. Due to its difficult economic situation, Cuba had neither the necessary insight nor the political strength to circumvent the detrimental genetic effects of imported radioactively contaminated foodstuffs after Chernobyl. We propose that the long term stable sex ratio increase in Cuba is essentially due to ionizing radiation.
A synoptic trend analysis of Russian and Cuban annual sex ratios discloses upward jumps in 1987. The estimated jump height from 1986 to 1987 in Russia measures 0.51% with a 95% confidence interval (0.28, 0.75), p value < 0.0001. In Cuba the estimated jump height measures 2.99% (2.39, 3.60), p value < 0.0001. The hypothesis may be tested by reconstruction of imports from the world markets to Cuba and by radiological analyses of remains in Cuba for Cs-137 and Sr-90.
If the evidence for the hypothesis is strengthened, there is potential to learn about genetic radiation risks and to prevent similar effects in present and future exposure situations.
男婴与女婴的出生比例可能是监测人口生殖健康的一种简单、非侵入性的方法。除了选择性堕胎导致性别比例偏差的社会之外，每 100 名女孩出生时大约有 105 名男婴。通常，在人口众多的情况下，出生时的人类性别比例非常稳定。1986 年 4 月切尔诺贝利核电站事故后，俄罗斯发现性别比例持续显著升高，即出生的男孩比预期的多，女孩比预期的少。最近，古巴也记录到 1987 年以来性别比例上升，并在科学文献中进行了讨论。
上世纪 80 年代末，古巴多达 60%的食品进口由前苏联提供。由于其经济困难，古巴既没有必要的洞察力，也没有政治力量来规避切尔诺贝利事件后进口放射性污染食品的有害遗传影响。我们提出，古巴长期稳定的性别比例上升主要是由于电离辐射。
对俄罗斯和古巴的年度性别比例进行综合趋势分析，揭示了 1987 年的上升趋势。俄罗斯从 1986 年到 1987 年的估计跳跃高度为 0.51%，95%置信区间（0.28，0.75），p 值<0.0001。古巴的估计跳跃高度为 2.99%（2.39，3.60），p 值<0.0001。该假设可以通过重建古巴从世界市场的进口以及对古巴的 Cs-137 和 Sr-90 残留进行放射性分析来检验。
如果该假设的证据得到加强，就有可能了解遗传辐射风险，并防止在当前和未来的暴露情况下出现类似的影响。
