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Maciamo
23-10-06, 10:23
In the book The History and Geography of Human Genes, by Cavalli-Sforza, Menozzi and Piazza (http://www.amazon.com/gp/product/0691029059/sr=8-1/qid=1155591683/ref=pd_bbs_1/104-9995679-7411115?ie=UTF8), it is mentioned that humans in some (previously) malaria-infected regions developed a resistance to malaria through a genetic change. Unfortunately this genetic change caused a hereditary disease known as thalassemia (http://en.wikipedia.org/wiki/Thallasemia), a form a blood anemia causing weakness, fatigue and lower activity levels (hence the appellation "lazy gene").

This disease is virtually absent from people of northern European ancestry, but prevalent in most other parts of the world, in varying proportions. There are different kinds of thallasemias : alpha, beta, delta, as well as the so-called sickle-cell disease (http://en.wikipedia.org/wiki/Sickle-cell_disease).


he estimated prevalence is 16% in people from Cyprus, 3-14 % in Thailand, and 3-8 % in populations from India, Pakistan, Bangladesh, and China. A lower prevalence has been reported from black people in Africa (0.9%) and northern Europe (0.1%).
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Sickle-cell disease occurs more commonly in people (or their descendants) from parts of the world, such as sub-Saharan Africa, where malaria is or was common.

The above-mentioned book has maps with the prevalence of each disease.

Alpha-thalassemia is mostly limited to the Arabic peninsula (Saudi Arabia, Yemen, Oman), Iran, and South-East Asia. In these regions over 20%, and sometimes over 40% of the population is affected. In a southern region of Nepal, 80% of the people suffer from -thalassemia, the highest percentage in the world ever observed.

In Europe, -thalassemia is almost only present in Greece and Southern Italy, with the highest percentage in Sardinia (over 8%) and Cyprus (4 to 6%). The highest prevalence world-wide are found in the Maghreb, West Africa, Ethiopia, Central Asia, and to a lower extent Southern India and Thailand, where it is comprised between 5 and 10% of the population.

I wonder how comes that this disease is not better known of the general population, e.g. through the media and education system. I had personally never heard of it before reading this book. Yet it explains a lot why people from hot countries have a tendency to be more lazy, even after migrating to colder climates. In Northern Europe, we are noticing higher unemployment rates among people of sub-saharan-African, Magreban and Southern Italian origins. Yet it is not true for people of (North) Indian or Chinese origin. One may think it is due to cultural differences, but why would "laziness" be a cultural trait ? I had long thought that it would be more likely an ethnic characteristic, linked to the genes, and this data on thalassemia has confirmed it in part. This also explains why Southern Italy has always lagged behind Northern Italy, despite all the efforts of the central government (itself more in the South) to erradicate such differences.

I would like to know more about the difference of effect between each type of thalassemia. I think that clues can be obtained by comparing the behaviour of people in the worst affected areas of a country or region, and compare them to much less affected regions of the same language and culture (like for Italy). This could also be done on an individual scale. Differences in behaviour between the Arabic-speaking Maghrebans and the Arabic-speaking Saudi or Yemeni are fairly obvious to ethnico-cultural observers. Given that the first group has a high prevalence of beta-thalassemia and the latter of alpha-thalassemia, it would be interesting to see how much of these behavioural differences are due to each type of thalassemia.

Black Africans suffer much more from sickle-cell disease than actual thalassemia. Could sickle-cell disease have stronger effects than thalassemia, so as to explain the extremely high inactivity level of Black Africans* ?

This is certainly worth researching, because if a correlation is found between thalassemia (or sickle-cell disease) and unemployment, governments could help sufferers of thalassemia with special health benefits. Treatments exist against anemia, like vitamins and minerals intake or blood transfusions. I suppose that in countries where thalassemia is almost inexistent, a worker with thalassemia would be fired more easily for its lower productivity. Again, special treatment could be given on grounds of medical condition (e.g. different timetable, different type of work, pay by task rather than per hour, etc.).

*most sub-saharan countries have unemployment rates over 30%, if not 50%

JackMack
09-06-09, 23:12
Your reasoning is flawed...the lack of energy might be related to having the various genes and illness mentioned but that does not exist in all the people of the regions you mentioned. That is a very racist statement. Laziness is not an inherited trait. If your theory were true then it would have to be in 100% of the population. Cultural differences and genetics are two totally separate things. Read on and learn....
Sickle cell is a mutation that developed as a beneficial mutation. People who have the trait in the heterozygous condition are immune to catching malaria- the parasite that lives in the Tse-tse fly cannot survive in an environment that has lower levels of oxygen. This lowered oxygen level is not enough to affect the individual who is a carrier of the disease but in the homozygous condition it can prove to be fatal- this is where it is a harmful mutational state for the carrier. Thallesemia is a different disease but similar to the Sickle Cell effect. Both diseases developed in countries where swamps bred a terrible host driven parasite but the Sickle trait was supposed to be a benefit.
What if I said that the terrible drug-addiction rate in some Northern European countries was due to a genetic flaw related to lower IQ levels or that all Italians are greasy and stupid because they all have black African DNA. Sterotypes have no basis in reality. Doesn't that sound ridiculous! I did not realize this was a racist site, Maciamo, and I'm very surprised by this post.

JackMack
09-06-09, 23:23
PS- Unemployment has nothing to do with laziness. Lazy people may be unemployed but the two are very, very different.

Maciamo
10-06-09, 21:48
Your reasoning is flawed...the lack of energy might be related to having the various genes and illness mentioned but that does not exist in all the people of the regions you mentioned. That is a very racist statement. Laziness is not an inherited trait. If your theory were true then it would have to be in 100% of the population. Cultural differences and genetics are two totally separate things. Read on and learn....

Have you read my post carefully ? Please quote what is think is not correct. It has been proven that sickle-cell anemia, as its name indicate, causes anemia, and therefore predispose people to low activity level, which is basically the definition of laziness. Hence sickle-cell anemia is one (but the the sole) cause of laziness, and sickle-cell anemia is inheritable.



Sickle cell is a mutation that developed as a beneficial mutation. People who have the trait in the heterozygous condition are immune to catching malaria- the parasite that lives in the Tse-tse fly cannot survive in an environment that has lower levels of oxygen. This lowered oxygen level is not enough to affect the individual who is a carrier of the disease but in the homozygous condition it can prove to be fatal- this is where it is a harmful mutational state for the carrier. Thallesemia is a different disease but similar to the Sickle Cell effect. Both diseases developed in countries where swamps bred a terrible host driven parasite but the Sickle trait was supposed to be a benefit.

Both diseases are beneficial against malaria, but not beneficial for activity levels since they cause anemia. These mutations are double-edged swords. They are necessary for survival in malaria-infested regions, but hamper economic development.



What if I said that the terrible drug-addiction rate in some Northern European countries was due to a genetic flaw related to lower IQ levels or that all Italians are greasy and stupid because they all have black African DNA.

Why would you say that if you have no scientific basis to support it ?

Maciamo
10-06-09, 21:50
PS- Unemployment has nothing to do with laziness. Lazy people may be unemployed but the two are very, very different.

Stating the obvious. What I meant (I thought it was evident) is that it is not surprising that unemployment should be high in a society affected on a large scale by anemia (a real medical condition making you feel energyless and therefore lazy).

JackMack
11-06-09, 18:46
Stating the obvious. What I meant (I thought it was evident) is that it is not surprising that unemployment should be high in a society affected on a large scale by anemia (a real medical condition making you feel energyless and therefore lazy).
A very small percentage of Italians and Greeks carry the Thallesemia gene. In the heterozygous condition there is no diminished energy capacity. In the people carrying the gene in the homozygous condition stress brings on a crisis- and they are not so tires that they can be considered lazy.

Your comments here are pure racist- Period. I would love to see some educated responses here. And yes, I have a masters degree in Genetics and I am an RN. Don't pretend to speak about this topic in an educated manner. You obviously do not have any knowledge about the topic which is evident by your unfounded assumptions.

I am sorry about being so upset on this topic but maybe your original post should have been in the form of a question about unemployment levels around Europe and not a post about a "lazy southern Italian" stereotype.

Where exactly are your people from? Maybe we can have a post about stereotypes and how untrue they are. For example, I recall physically seeing many more blond/ red haired, blue/ green eyed Italian people in Sicily then in northern and Central Italy. Could it be another stereotype about southern Italians being all dark as false? Your "beliefs" are not the proven truth. For example, my German (transplants from Germany recently) friends here in the USA do not ascribe to this thinking. They believe that the Greco-Romans (yes, I carefully used that term) had many blond/ blue individuals among them, not admixed with Germans - along with the Estruscans. For God's sake- even Adolph Hitler believed that the ancient Greeks were Aryans in his twisted thinking- I believe some scientists state that the J2 individuals' DNA came from the ancient Greeks- which were not any darker then the rest of Europe at the time. Until we see some genetic evidence to otherwise prove or not any stereotype we should all refrain from making those comments.

Maciamo
13-06-09, 12:53
Your comments here are pure racist- Period.

JackMack, shall I understand by your comment that you consider northern and southern Italians to be different races ? I do not.

If by racist you mean that I accept that humans were NOT created equal as some Christians stupidly believe, then call me racist. Genetic differences do exist between individuals and run in some families or regions, and genetics do have an influence of personality and energy levels.

Some genetic differences are found only in some families, other in some ethnic or sub-ethnic group, other roughly in continental groups (e.g. Europeans or Africans or Native Americans), but a big part of genetic variants in humans are spread more or less evenly in every ethnic group on Earth.

I was just wondering here if malaria-resistance caused anemia (a region-specific genetic variant found in tropical region affected by malaria) could explain the lower economic activity in hotter climates. It is surely not the only factor, but I also doubt that it has no influence at all.



Maybe we can have a post about stereotypes and how untrue they are. For example, I recall physically seeing many more blond/ red haired, blue/ green eyed Italian people in Sicily then in northern and Central Italy. Could it be another stereotype about southern Italians being all dark as false?

What does this have to do with malaria resistance and anemia ? I am not talking about stereotypes here but facts. Unemployment is higher and GDP per capita is lower in southern Italy than in northern Italy and this has been like this for many centuries.

As for blond and blue-eyed Sicilians, keep in mind that there was an important Norman settlement in north-west Sicily in the middle ages. South-east and North-west Sicilians have quite different Y-DNA haplogroups and look quite different too.

JackMack
16-06-09, 21:07
JackMack, shall I understand by your comment that you consider northern and southern Italians to be different races ? I do not.
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No- They are not seperate races- never said that nor implied that- maybe you did....?
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If by racist you mean that I accept that humans were NOT created equal as some Christians stupidly believe, then call me racist. Genetic differences do exist between individuals and run in some families or regions, and genetics do have an influence of personality and energy levels.
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Genetic differences exist - placing a racist label on them is wrong.
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Some genetic differences are found only in some families, other in some ethnic or sub-ethnic group, other roughly in continental groups (e.g. Europeans or Africans or Native Americans), but a big part of genetic variants in humans are spread more or less evenly in every ethnic group on Earth.
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no kidding....
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I was just wondering here if malaria-resistance caused anemia (a region-specific genetic variant found in tropical region affected by malaria) could explain the lower economic activity in hotter climates. It is surely not the only factor, but I also doubt that it has no influence at all.
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The answer is no- it doesnt. Period. What don't you get? Most of these people do not carry the gene- what's your point...

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What does this have to do with malaria resistance and anemia ? I am not talking about stereotypes here but facts. Unemployment is higher and GDP per capita is lower in southern Italy than in northern Italy and this has been like this for many centuries.
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This may or may not be true but one thing is for sure- malaria has nothing to do with it.

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As for blond and blue-eyed Sicilians, keep in mind that there was an important Norman settlement in north-west Sicily in the middle ages. South-east and North-west Sicilians have quite different Y-DNA haplogroups and look quite different too.
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There were blond/ blue people on the island before the Normans.

Maciamo
17-06-09, 10:32
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There were blond/ blue people on the island before the Normans.

Well, of course, through the Italo-Celtic R1b that invaded the Italian peninsula around 3,200 years ago. But blond hair quickly become diluted when mixed with very dark haired people (like the E1b1b and J who have dominated southern Italy since the Neolithic). It's not a coincidence that light hair (http://www.eupedia.com/europe/maps_of_europe.shtml#hair_colour) is more common nowadays in parts of Sicily settled by the Normans.

JackMack
27-06-09, 17:47
Well, of course, through the Italo-Celtic R1b that invaded the Italian peninsula around 3,200 years ago. But blond hair quickly become diluted when mixed with very dark haired people (like the E1b1b and J who have dominated southern Italy since the Neolithic). It's not a coincidence that light hair (http://www.eupedia.com/europe/maps_of_europe.shtml#hair_colour) is more common nowadays in parts of Sicily settled by the Normans.

You speak like an authority but are full of misinformation. What is your educational background? I suspect a self proclaimed expert in genetics with no university training. I guess you get your information only from the internet.

Maciamo
28-06-09, 14:10
You speak like an authority but are full of misinformation. What is your educational background? I suspect a self proclaimed expert in genetics with no university training. I guess you get your information only from the internet.

I was correcting you about history. This discussion has little to do about the genetics taught at university, believe me. Frankly, what university is going to teach you about the percentage of blond hair in Sicily ? :rolleyes2:

I am used to people like you who suddenly become aggressive (calling me a racist out of the blue) when they can't find any valid argument, then bring forward their "qualifications" as if it was an argument in itself... The fact that you behave like this while avoiding to address my remarks make me doubt your sincerity. Are you even a geneticist as you claim ? How could I be sure ? What difference does it make if you obviously don't know what you are talking about ?

JackMack
22-08-09, 00:11
I was correcting you about history. This discussion has little to do about the genetics taught at university, believe me. Frankly, what university is going to teach you about the percentage of blond hair in Sicily ? :rolleyes2:

I am used to people like you who suddenly become aggressive (calling me a racist out of the blue) when they can't find any valid argument, then bring forward their "qualifications" as if it was an argument in itself... The fact that you behave like this while avoiding to address my remarks make me doubt your sincerity. Are you even a geneticist as you claim ? How could I be sure ? What difference does it make if you obviously don't know what you are talking about ?

This discussion for me is over- you are a racist which your comments above prove. I've directly addressed your remarks. You have made comments based on your own beliefs and not fact. Even the fact that you pose such a topic is proof in itself of your extreme ignorance.

Cambrius (The Red)
22-08-09, 06:54
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There were blond/ blue people on the island before the Normans.

Yes, I suspect there may well have been some blonds in Sicily prior to the Norman invasion. The Normans were a ruling MINORITY and probably made only minor genetic contributions to the Sicilian population.

Blonds are not exclusive to Nordic peoples. For example, the ancient Berbers (and what remains of their unmixed descendants) have a high percentage of blonds and light brunettes. They actually nave a greater number of light-eyed people than some regions of Europe.

Also, read up on the Guanches of the Canary Islands...

Algernon
13-10-12, 16:08
Thanks for sharing.

nordicwarrior
29-11-12, 05:09
Maciamo, if you are still reading this thread...Thalassemia is no joke. I have seen first hand what it can do to a person very close to me. Originally this was a beneficial mutation to deal with the malaria, but it side effects can absolutely wipe away a person's energy levels. There really isn't a cure, the blood transfusions are more of a stop gap. Minor is bad enough, Thalassemia Major can be fatal if not addressed early.