最近，美国科学院院报（PNAS）发表了两篇有关生物行为的最新研究论文，一篇是在成年人中做的“婚配”情况的调查，另一篇是在果蝇中做的“口味”现象的研究。 有趣的是，科学家发现，人们在找对象时，倾向于找跟自己DNA相似的人。在825对美国非西班牙裔白人夫妇中，调查了配偶之间多达170万个单核苷酸多态性（SNP）差异。 调查发现，夫妇之间按基因相似性结合的所谓“基因选配”（genetic assortative mating）的机率比根据教育程度相似性结合的“教育选配”（educational assortative mating）的机率高三分之一。 不过，科学家承认，还不知道其他种族中是否也存在这种现象，也不知道人们在交朋友时是否也找基因相似的人。 一句话问倒科学家：兄妹之间的DNA相似，难道他们很想结成夫妻？ 按常识，男女之间性格近似者比较和谐，因为彼此心有灵犀，容易理解对方。至于家庭背景、教育程度、经济状况等，也对婚姻关系有重要影响，即所谓“门当户对”。经验表明，性格是不能遗传的，至少遗传不是决定性格的主要因素，不然也不会有“一娘生九子，九子九个样”的说法了！ 以下是该文来源及链接： Benjamin W. Domingue, Jason Fletcher, Dalton Conley, and Jason D. Boardman. Genetic and educational assortative mating among US adults . PNAS , May 19, 2014 DOI: 10.1073/pnas.1321426111 ScienceDaily的相关报道： I like your genes: People more likely to choose a spouse with similar DNA Date: May 19, 2014 Source: University of Colorado at Boulder Summary: Individuals are more genetically similar to their spouses than they are to randomly selected individuals from the same population, according to a new study. Scientists already knew that people tend to marry others who have similar characteristics, including religion, age, race, income, body type and education, among others. Scientists now show that people also are more likely to pick mates who have similar DNA. Individuals are more genetically similar to their spouses than they are to randomly selected individuals from the same population. Credit: abhijith3747 / Fotolia Individuals are more genetically similar to their spouses than they are to randomly selected individuals from the same population, according to a new study from the University of Colorado Boulder. Scientists already knew that people tend to marry others who have similar characteristics, including religion, age, race, income, body type and education, among others. In the new study, published in the journal Proceedings of the National Academy of Sciences , scientists show that people also are more likely to pick mates who have similar DNA. While characteristics such as race, body type and even education have genetic components, this is the first study to look at similarities across the entire genome. It's well known that people marry folks who are like them, said Benjamin Domingue, lead author of the paper and a research associate at CU-Boulder's Institute of Behavioral Science. But there's been a question about whether we mate at random with respect to genetics. For the study, Domingue and his colleagues, including CU-Boulder Associate Professor Jason Boardman, used genomic data collected by the Health and Retirement Study, which is sponsored by the National Institute on Aging. The researchers examined the genomes of 825 non-Hispanic white American couples. They looked specifically at single-nucleotide polymorphisms, which are places in their DNA that are known to commonly differ among humans. The researchers found that there were fewer differences in the DNA between married people than between two randomly selected individuals. In all, the researchers estimated genetic similarity between individuals using 1.7 million single-nucleotide polymorphisms in each person's genome. The researchers compared the magnitude of the genetic similarity between married people to the magnitude of the better-studied phenomenon of people with similar educations marrying, known as educational assortative mating. They found that the preference for a genetically similar spouse, known as genetic assortative mating, is about a third of the strength of educational assortative mating. The findings could have implications for statistical models now used by scientists to understand genetic differences between human populations because such models often assume random mating. The study also forms a foundation for future research that could explore whether similar results are found between married people of other races, whether people also choose genetically similar friends, and whether there are instances when people prefer mates whose DNA is actually more different rather than more similar. 另一项令人匪夷所思的发现是，苦味是短命之味，而甜味则是长寿之味。更有甚者，尝不出水味者寿命延长43%！ 对于为何尝不出水味者长寿的理由，科学家的解释是：可能试图通过贮存大量脂肪来补偿所感知的水短缺，并在随后利用这些贮存脂肪产生内源水。 第一句话问倒科学家：肥胖导致多种炎性后遗症，岂有长寿之理？ 第二句话问倒科学家：糖尿病人吃糖，也能延寿？ 研究已经表明，肥胖者的“舌尖”不敏感，吃甜不厌，吃肥不腻，吃多不饱，结果导致大量脂肪贮存，进而触发慢性炎症，引起多种代谢性疾病，绝对无长寿可能。糖尿病是肥胖的后遗症之一，他们应尽量避免吃甜食，防止血中葡萄糖水平升高，否则犹如“雪上加霜”，会让病情加重。 以下是该文来源及链接： M. J. Waterson, B. Y. Chung, Z. M. Harvanek, I. Ostojic, J. Alcedo, S. D. Pletcher. Water sensor ppk28 modulates Drosophila lifespan and physiology through AKH signaling . Proceedings of the National Academy of Sciences , 2014; DOI: 10.1073/pnas.1315461111 ScienceDaily的相关报道： Taste test: Could sense of taste affect length of life? Date: May 19, 2014 Source: University of Michigan Health System Summary: Perhaps one of the keys to good health isn't just what you eat but how you taste it. Taste buds -- yes, the same ones you may blame for that sweet tooth or French fry craving -- may in fact have a powerful role in a long and healthy life -- at least for fruit flies. Bitter tastes could have negative effects on lifespan, sweet tastes had positive effects, and the ability to taste water had the most significant impact -- flies that could not taste water lived up to 43% longer than other flies. Perhaps one of the keys to good health isn’t just what you eat but how you taste it. Credit: Alliance / Fotolia Perhaps one of the keys to good health isn't just what you eat but how you taste it. Taste buds -- yes, the same ones you may blame for that sweet tooth or French fry craving -- may in fact have a powerful role in a long and healthy life -- at least for fruit flies, say two new studies that appear in the Proceedings of the National Academy of Sciences of the United States of America . Researchers from the University of Michigan, Wayne State University and Friedrich Miescher Institute for Biomedical Research in Switzerland found that suppressing the animal's ability to taste its food -regardless of how much it actually eats -- can significantly increase or decrease its length of life and potentially promote healthy aging. Bitter tastes could have negative effects on lifespan, sweet tastes had positive effects, and the ability to taste water had the most significant impact -- flies that could not taste water lived up to 43% longer than other flies. The findings suggest that in fruit flies, the loss of taste may cause physiological changes to help the body adapt to the perception that it's not getting adequate nutrients. In the case of flies whose loss of water taste led to a longer life, authors say the animals may attempt to compensate for a perceived water shortage by storing greater amounts of fat and subsequently using these fat stores to produce water internally. Further studies are planned to better explore how and why bitter and sweet tastes affect aging. This brings us further understanding about how sensory perception affects health. It turns out that taste buds are doing more than we think, says senior author of the University of Michigan-led study Scott Pletcher, Ph.D., associate professor in the Department of Molecular and Integrative Physiology and research associate professor at the Institute of Gerontology. We know they're able to help us avoid or be attracted to certain foods but in fruit flies, it appears that taste may also have a very profound effect on the physiological state and healthy aging. Pletcher conducted the study with lead author Michael Waterson, a Ph.D graduate student in U-M's Cellular and Molecular Biology Program. Our world is shaped by our sensory abilities that help us navigate our surroundings and by dissecting how this affects aging, we can lay the groundwork for new ideas to improve our health, says senior author of the other study, Joy Alcedo, Ph.D, assistant professor in the Department of Biological Sciences at Wayne State University, formerly of the Friedrich Miescher Institute for Biomedical Research in Switzerland. Alcedo conducted the research with lead author Ivan Ostojic, Ph.D., of the Friedrich Miescher Institute for Biomedical Research in Switzerland. Recent studies suggest that sensory perception may influence health-related characteristics such as athletic performance, type II diabetes, and aging. The two new studies, however, provide the first detailed look into the role of taste perception. These findings help us better understand the influence of sensory signals, which we now know not only tune an organism into its environment but also cause substantial changes in physiology that affect overall health and longevity, Waterson says. We need further studies to help us apply this knowledge to health in humans potentially through tailored diets favoring certain tastes or even pharmaceutical compounds that target taste inputs without diet alterations. 尽信论文，不如无论文！ 迷信科学，不如无科学！ 旧情难了（楼宏章） 月光（胡彦斌）
口味的形成 Flavor or flavour is the sensory impression of a food or other substance, and is determined mainly by the chemical senses of taste and smell. 甜、酸、苦、咸和香味 其中，甜、香、苦味与分子和味蕾表面细胞膜中G蛋白偶联的受体结合产生这三种“味道” 咸是碱金属进入味蕾细胞后产生的味觉，类似，酸味则是氢离子进入味蕾细胞内之后产生的味道。 经过长期的“关联”，人类的味觉与食物分子的种类具有对应关系，比如“甜”，对应富含能量的食物；苦味则与有毒物质关联 每个味蕾含有50~100个味觉受体细胞， 味觉感知能力随着年龄的增长而消减； 大约每20年消减半数
标签: 口味
