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Post by djoser-xyyman on Jul 6, 2017 12:18:08 GMT -5
Mechanisms of phenotype evolution Detecting balancing selection as a maintenance mechanism of psychiatric disorders within human populations. Daiki Sato 1,*, Abstract: Recently, growing attention has been paid to evolutionary psychiatry, where the evolutionary mechanisms behind the prevalence of psychiatric disorders have been discussed. Though mental health problem has become very common in our modern society, it is hard to explain this phenomenon because maladaptive features should have been removed from population over the course of evolution. To answer this question, we tested a hypothesis that psychiatric disorders-risk alleles have been maintained within populations by natural selection. Out of 1,013 psychiatric disorders-relevant genes, four genes, CLSTN2, FAT2, VMAT1 and ZBBX, have been detected as positively selected genes in human lineage. Among them, VMAT1, vesicular monoamine transporter 1, was particularly interesting since it has a human-unique polymorphism (Thr/Ile) in the 136th amino acid site compared to other mammals (Asn). In addition, 136Ile has been proposed to be linked to bipolar disorder and anxiety although the allele could be found at relatively high frequencies (20-40%) in non-African populations. In non-African populations, Tajima’s D value showed a significant peak centering around Thr136Ile, suggesting that this polymorphism has been maintained by balancing selection. Our study demonstrates an evolutionary mechanism behind psychiatric disorders and provides insights into the evolution of diseases. Expanded summary*: Psychiatric disorders, such as schizophrenia, depression and autism, can be seen at relatively high incidence (1-20%) all over the world. It has been known that genetic components greatly contribute to their onset, and that those disorders do degrade patients’ quality of life. However, why and how the causative genes have been maintained within current human populations still remains to be elucidated. Revealing its mechanisms is of particular importance not only from the evolutionary perspective but for medical treatment of those disorders. In regard to this question, we focused on a human-unique polymorphism (Thr/Ile) in the 136th amino acid site of VMAT1 gene, vesicular monoamine transporter 1, detected by the sequence comparison using mammal genome data. This gene encodes the protein importing monoamine, such as serotonin or dopamine, into presynaptic vesicles and mediates neurotransmission. 136Ile has been proposed to be linked to psychiatric disorders such as bipolar disorder or anxiety, but 1000 Genomes Data showed that 136Ile exists at relatively high frequencies (20-40%) in all but African populations. The results of Tajima’s D values indicated that the allelic polymorphism (136Thr/Ile) has been maintained by balancing selection, such as negative frequency-dependent selection, heterozygote advantage or spatially variable finesses. Moreover, the analysis using coalescent simulations revealed that 136Ile originated around 100,000 years ago, generally regarded as the timing of Out of Africa event by modern humans, giving us insight on the relationship between Out of Africa event and the prevalence of psychiatric disorders in modern humans. Our results suggest that polymorphic alleles causing psychiatric disorders could have been maintained by balancing selection, and that a genetic change coinciding with the global spread of modern humans might have contributed to the risk prevalence of those disorders.
As I said….Europeans are a subset of Africans and the pattern is clinal. Ie North to North
Local adaptation of a human cold receptor along a latitudinal cline - Felix Key 1 2, Abstract: Ambient temperature is a critical environmental factor, and persistent cold likely a major challenge as early modern humans first colonized high-latitude non-African environments. A few local adaptations have been identified in subarctic human populations, mostly involving metabolic changes in response to local diets. As of yet, though, we know of no genetic adaptation to temperature perception. Using a battery of tools we show that TRPM8, the gene that encodes the TRP cation channel that mediates cold perception, evolved under local positive selection in populations living at moderate to high latitudes. The derived allele of upstream SNP rs10166942 shows unusually high population differentiation, with frequencies that range from 5% in Nigeria to 88% in Finland; in fact, its frequency correlates significantly with latitude and temperature beyond what can be explained by population history, both in the 1000 Genomes and the SGDP datasets. A sophisticated Bayesian approach revealed that the allele was neutral in Africa and, after the out-of-Africa bottleneck, it was differentially targeted by positive selection across Eurasian populations. Interestingly, rs10166942 *****ancestral allele ****has been associated with protective effects from migraine, a debilitating disorder that has its highest prevalence in individuals of European descent. Local adaptation on previously neutral standing variation may thus have influenced not only temperature perception, but also the risk of pain phenotypes in certain human populations.
More African genes needed?
-------------- African ROH Drive Enrichment of Deleterious Alleles in a Sample of Admixed Individuals Zachary Szpiech*, Angel Mak, Marquitta White, Donglei Hu, Celeste Eng, Esteban Burchard, Ryan Hernandez Abstract: Runs of homozygosity (ROH) are important genomic features that manifest when identical-by-descent haplotypes are inherited from parents. Their length distributions are informative about population history, and their genomic locations are useful for mapping recessive loci contributing to both Mendelian and complex disease risk. We have previously shown that ROH, and especially long ROH that are likely the result of recent parental relatedness, are enriched for homozygous deleterious coding variation in a worldwide sample of outbred individuals (Szpiech, et al. 2013). However, the distribution of ROH in admixed populations and their relationship to deleterious homozygous genotypes is understudied. Here we analyze whole genome sequencing data from 1,484 individuals from African American, Puerto Rican, and Mexican American populations. These populations are three-way admixed between European, African, and Native American ancestries and provide an opportunity to study the distribution of deleterious alleles partitioned by local ancestry and ROH. We re-capitulate previous findings that long ROH are enriched for deleterious variation genome-wide. Then, partitioning by local ancestry, we compare the proportion of deleterious homozygotes in ROH comprised of single ancestry haplotypes to the proportion of benign homozygotes in those ROH. We find that ROH falling in African ancestry tracts are enriched the most followed by European and Native American ROH. These results suggest that, while ROH on any haplotype background are associated with an inflation of deleterious homozygous variation, African haplotype backgrounds may play a particularly important role in the genetic architecture of complex diseases for admixed individuals, highlighting the need for further population genetic study of these populations
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Post by anansi on Jul 6, 2017 13:45:22 GMT -5
I have to go with nurture over nature, environmental stresses cause ppl to do violent even crazy things, sometimes embedded in a particular culture, eg the social history of far north countries like Denmark, Sweden,Switzerland, Norway etc made for some of the most violent prone societies in their histories, aka Vikings and their habits, but notice with increased productivity and changes in culture they are among the most peaceful today and mong the most inviting places to live, medieval Mali was among the most peaceful tranquil places to live and do business in, crime and casual violence was unheard of, but they were among the richest and highly educated societies of their time vs today where there are tourist warnings and travel advisories. Change the environment and culture,that is what change the behavior.
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Post by kel on Jul 28, 2017 14:03:22 GMT -5
It is genetic.
Euros are a subset of Afros and populated by those who left.
The Afros who remained have way higher genetic diversity and show higher levels of mutations.
mutations = evolution according to Darwin. Therefore, Africans are literally the most evolved.
Euros are the least evolved meaning that they of all the "races" retain the highest percentage of archaic traits.......traits that have evolved out of Africans.
psychiatric disorders, sexual disorders, emotional disorders, sociopathic tendencies, extreme xenophbia, etc....
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Post by autshumato on Aug 7, 2017 1:44:50 GMT -5
It is genetic. Euros are a subset of Afros and populated by those who left. The Afros who remained have way higher genetic diversity and show higher levels of mutations. mutations = evolution according to Darwin. Therefore, Africans are literally the most evolved. Euros are the least evolved meaning that they of all the "races" retain the highest percentage of archaic traits.......traits that have evolved out of Africans. psychiatric disorders, sexual disorders, emotional disorders, sociopathic tendencies, extreme xenophbia, etc.... Modern Europeans are Albinos of the Dravidian people.
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Post by kel on Aug 9, 2017 20:00:10 GMT -5
whatever they are: they are carrying remnants of archaic traits: the extreme anti-social behavior. also, Its possible that the albinism is a contributing factor as well - insufficient levels of melanin leading to mental issues.
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Post by djoser-xyyman on Jun 22, 2018 7:02:27 GMT -5
No they are not whatever they are: they are carrying remnants of archaic traits: the extreme anti-social behavior. also, Its possible that the albinism is a contributing factor as well - insufficient levels of melanin leading to mental issues.
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Post by kel on Jun 22, 2018 10:28:08 GMT -5
Trump and Sessions ? psychopathic white behavior ??
genetic: carrying archaic traits OR a result of melanin deficiency in the brain.
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Post by djoser-xyyman on Jun 22, 2018 10:47:34 GMT -5
Yes, we know it is tied to melanin deficiency. Also it is a genetic disorder as I pointed out in this thread. But they are not Dravidians..Albinos. Kefi pointed out in her diseases studies that North Africans carry the “founder” genes for many of the genetic disorders that ail many modern Europeans. Europeans are not Dravidian Albinos. They are a subset of Africans(Tishkoff et al)…depigmented Africans. Trump and Sessions ? psychopathic white behavior ?? genetic: carrying archaic traits OR a result of melanin deficiency in the brain.
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Post by kel on Jun 22, 2018 11:34:16 GMT -5
hmmm
you and Mike have to duke it out...........
haven't heard from him in a while....has he been banned ?
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Post by djoser-xyyman on Jun 22, 2018 12:02:12 GMT -5
Looks like he is banned. Don't agree with it...but he is a big boy.
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Post by anansi on Jun 23, 2018 6:43:32 GMT -5
Looks like he is banned. Don't agree with it...but he is a big boy. He was given a one month chill out period which expired quite sometime ago. Like u said he's a big boy.
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Post by anansi on Jun 23, 2018 6:54:18 GMT -5
@ kel {said: Trump and Sessions ? psychopathic white behavior ??
genetic: carrying archaic traits OR a result of melanin deficiency in the brain} But what would explain the Bokassas or Pol Pots of the melaninated world.
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Post by zarahan on Jun 24, 2018 23:23:00 GMT -5
I don't agree with extreme claims attributing all violence in Europeans to a genetic disposition. Like you say the ere are just too many "nurture" or environmental variables, to reduce all to a simplistic, one-dimensional explanation. But the xyz data is just as valid as those of other studies purporting to examine genetic causes of violence among groups advanced by Linda Gottfredson, JP Rushton and others of the "hereditarian" crowd.
If they want to play that game- it can go both ways- and the spotlight turned on European violence patterns- even, steven. SOme of these people are busy trying to come up with a "black violence gene" to "explain" this and that. They came up with what they thought was a "smoking gun" in higher levels of testosterone among some black offenders, and it looked good, only when the data is examined various bogus claims fell apart. Turns out that the biggest purveyors of violence- whites and Asians, have LOWER levels of testosterone than those evil blacks. Nice folk like those nice Germans (17 million murdered by the Fuherer, and 12 million or so by "role model" Joseph Stalin). As for the allegedly "mo peaceful" Asians (some 40-60million murdered by smiling CHairman Mao, and a "mere" 1-2 million by Pol POt in Cambodia, about 25% of his country's population). But hey, what's a few ten million between friends?
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Post by zarahan on Jun 25, 2018 0:10:56 GMT -5
There are a number of genetic and neurological markers at work, some associated with environmental factors. Quote:
"There is evidence to suggest that certain types of genetic risk for antisocial behaviors and externalizing disorders may be consistent between individuals of Asian descent and those of European descent. For instance, diminished serotonergic activity may increase sensitivity to stimuli that elicit provocation and aggression and decrease sensitivity to stimuli associated with punishment (Spoont, 1992). Low serotonergic activity is associated with greater aggressive behavior in European American and Asian groups (Lee & Coccaro, 2001). Serotonergic transmitter dysfunction associated with aggression and conduct disorder has been identified on chromosome 17ql2 region. In a sample of 153 European American male forensic patients, the 5-HTTLPR S allele at the 17ql2 site (a polymorphism within the 5HT transporter promoter gene involved in serotonin function) was more commonly found among those with recurrent violent behavior (Retz et al., 2004).
The 17q 12 chromosomal region was also implicated in conduct disorder studies including 249 adolescents from consecutive admissions to treatment facilities for substance abuse and delinquency and their siblings and 4,493 community adolescents (Stallings et al., 2005). Liao, Hong, Shih, and Tsai (2004) also identified SLC64 as a possible candidate serotonin transporter gene at the 17q 12 loci. In their study of 169 criminals and 111 community controls in Taiwan, violent criminals were identified as having a higher frequency of the 5-HTTLPR S allele than controls.
Because of the role of dopamine in brain reward and approach systems, some researchers have postulated associations between dopamine regulation, antisocial behaviors, and novelty-seeking. There is some evidence of DRD2 and DRD4 as candidate genes associated with conduct disorder in European American samples (Rowe et al., 2001) and DRD2 with conduct disorder in Han Chinese samples (Lu, Lee, Ko, & Lin, 2001)...
Despite this seemingly robust finding, the association of low MAO-A activity and antisocial behavior was not replicated in an Asian sample. In a cohort of 631 males and females studied from childhood to adulthood, Widom and Brzustowicz (2006) found that the interaction of low MAO-A activity and childhood maltreatment (court-substantiated child abuse and neglect) was associated with violent and antisocial behavior (arrests, self-report, diagnoses) among European American participants, but not among non-European Americans (African Americans, Latino/a Americans, American Indians, and Pacific Islanders)."
-- Edward C. Chang. 2012. Handbook of Adult Psychopathology in Asians: Theory, Diagnosis, and Treatment
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Post by Deleted on Jun 25, 2018 3:52:17 GMT -5
" As for the allegedly "mo peaceful" Asians (some 40-60million murdered by smiling CHairman Mao, and a "mere" 1-2 million by Pol POt in Cambodia, about 25% of his country's population). But hey, what's a few ten million between friends?" 40-60 million murdered? How? when? People did starve during "The Great Leap Forward" policy due to poor organization not murder. As for the numbers bandied about, they are based on the number of people who would have been born if the famine had not occurred and the number of people who died of starvation.
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