Appearance of Sicilians relative to other Mediterraneans? (poll included)

[oreo_cookie]

If Dienekes' work essentially comes to the same conclusions as professional studies, I think it can be used as a guide to understanding population genetics but not as a definite, end-all answer for the simple reason of sample sizes being dependent on who decides to submit their data, thus you would need approximately the same number of each ethnic group to make definitive conclusions.

 

[Cambrius (The Red)]

Professional geneticists have openly praised the Eurogenes and Dodecad projects for professionalism and accuracy - the journal Nature and others.

Read the article in the 15th December issue of the Nature Journal, "Rise of the Genome Bloggers". I'll try and locate other material.

http://www.nature.com/news/2010/101215/full/468880a.html?s=news_rss

 

[oreo_cookie]

Professional geneticists have openly praised the Eurogenes and Dodecad projects for professionalism and accuracy - the journal Nature and others.

Read the article in the 15th December issue of the Nature Journal, "Rise of the Genome Bloggers". I'll try and locate other material.

http://www.nature.com/news/2010/101215/full/468880a.html?s=news_rss

The results I've seen from them always seem sensible and accurate, I just was concerned about the sample sizes that's all.

 

[Dorianfinder]

The results I've seen from them always seem sensible and accurate, I just was concerned about the sample sizes that's all.

For a study to be valid it needs to test only what is intended. The sample sizes are too small leaving too much room for confounding variables to effect the results. The generic problem with much of this commercial and internet DNA research is that many results are duplicated giving a false impression of reliability (similar outcomes) when in fact the same people circulate ftdna, 23and me and eupedia forums and data is shared as studies often piggy back on each others' results.

 

[Knovas]

There are sample populations with a few individuals, which is for example the case of the Greek one (I must admit). But if you check Spaniards, Italians, CEU, and even the British and the Irish populations (Cornish and Kent included), you'll see there are enough participants to get an accurate idea.

And samples are still increasing, so don't worry for this since some populations already have quite samples, and even more will be added. Also, don't forget the fact that it's a good comparative data, specially, taking the largest sample sizes as reference. I mean that populations are often under the same conditions (having quite samples), and what you can see comparing each other, for sure it's not noise.

At some level, to continue adding samples does not change the average results. At least, not drastically.

 

[Cambrius (The Red)]

There are sample populations with a few individuals, which is for example the case of the Greek one (I must admit). But if you check Spaniards, Italians, CEU, and even the British and the Irish populations (Cornish and Kent included), you'll see there are enough participants to get an accurate idea.

And samples are still increasing, so don't worry for this since some populations already have quite samples, and even more will be added. Also, don't forget the fact that it's a good comparative data, specially, taking the largest sample sizes as reference. I mean that populations are often under the same conditions (having quite samples), and what you can see comparing each other, for sure it's not noise.

At some level, to continue adding samples does not change the average results. At least, not drastically.

The Eurogenes and Dodecad data essentially mirrors results from the most recent institutional autosomal studies (e.g., Gayan and Behar 2009 / 2010, also the Dr. McDonald team, among others).

 

[oreo_cookie]

The thing I wanted to see, as far as Dodecad goes, is to have Iberian samples divided by region, to get a good picture of how say, Madeirenses differ from continental Portuguese, and now Andalusians, Catalans, Galicians etc. compare to one another, the same way he has Italy divided into three or more groups.

 

[Cambrius (The Red)]

The thing I wanted to see, as far as Dodecad goes, is to have Iberian samples divided by region, to get a good picture of how say, Madeirenses differ from continental Portuguese, and now Andalusians, Catalans, Galicians etc. compare to one another, the same way he has Italy divided into three or more groups.

There certainly are some regional differences in haplogroup frequencies but that really means little in terms of full ancestry scores.

You have to be very careful with certain areas to determine if samples qualify as representative of the indigenous population. As you may know, there is the infamous case of the Alcacer do Sal (Alentejo) haplogroup testing (Pereira 2005 and 2010). Alcacer do Sal was virtually isolated from neighboring towns for hundreds of years since it was a malaria zone and populated by social outcasts such as ex-slaves and leprosy and contagious disease victims. Consequently, these people were forced to practice endogamy and their gene pool cannot be seen as indigenously representative. The same can be said for the Canaries.

 

[Dorianfinder]

At some level, to continue adding samples does not change the average results. At least, not drastically.

More so for homogeneous populations than the Balkans, they don't call it a Macedonian salad for nothing.:bored:

 

[oreo_cookie]

You have to be very careful with certain areas to determine if samples qualify as representative of the indigenous population. As you may know, there is the infamous case of the Alcacer do Sal (Alentejo) haplogroup testing (Pereira 2005 and 2010). Alcacer do Sal was virtually isolated from neighboring towns for hundreds of years since it was a malaria zone and populated by social outcasts such as ex-slaves and leprosy and contagious disease victims. Consequently, these people were forced to practice endogamy and their gene pool cannot be seen as indigenously representative. The same can be said for the Canaries.

I'd like to see how Madeira compares, i.e. if there is more West African than on the mainland, and if the Flemish influence in the Azores was strong enough to pull them genetically toward Northern Europe.

 

[Knovas]

We have already been talking about outliers. Almost everywhere, you can always find the main population and others who deviate but are linked. Checking populations with highly homogeneous individuals it's very easy to understand, and more samples don't affect the average when quite are listed.

Probably checking Balkans it's necesary to make several divisions to see the different homogeneous groups, since as a whole the visual effect it's obvious. The same happens in Italy and Russia, this one surely at higher scale (the participants listed are from the European side, just a few near the Urals start to deviate).

In situations like this, I agree that more samples are required, althought some cases as for example the Italians, actually have quite samples from the different regions. Dienekes always tries to separate groups when they show special characteristics, so he probably will do it as more samples come, allowing him to create new groups/sub-groups.

 

[oreo_cookie]

Some more pictures, in reference to the thread/poll (Sicilians from various parts of the island) but other productive discussion can still continue.

 

[Dorianfinder]

I'd like to see how Madeira compares, i.e. if there is more West African than on the mainland

Any North-West African influence should be minimal. There is however the real possibility that Angolan and Mozambican colonialists may have brought some Sub-Saharan influence back with them. There is a significant population in South Africa that keep regular contact with home.

 

[oreo_cookie]

Any North-West African influence should be minimal. There is however the real possibility that Angolan and Mozambican colonialists may have brought some Sub-Saharan influence back with them. There is a significant population in South Africa that keep regular contact with home.

I was thinking of coastal West African (Senegambian) influence, since in the early days of settlement, the Portuguese brought slaves from that region to Madeira to work on sugar plantations.

 

[Dorianfinder]

I was thinking of coastal West African (Senegambian) influence, since in the early days of settlement, the Portuguese brought slaves from that region to Madeira to work on sugar plantations.

Any offspring would look variably different to your typical Madeiran, this was a relatively recent introduction and is contrasted with the fact that Portugal and the Atlantic coast of Europe lies close by. Unlike the VOC's trading posts founded in the Cape of Good Hope and Malabar.

 

[oreo_cookie]

Any offspring would look variably different to your typical Madeiran, this was a relatively recent introduction and is contrasted with the fact that Portugal and the Atlantic coast of Europe lies close by. Unlike the VOC's trading posts founded in the Cape of Good Hope and Malabar.

But slaves were in Madeira in the 1500s through the 1700s (after which they probably blended into the population) so I'd expect a diluted amount of West African to be present in the population since. I may be wrong, though.

 

[Cambrius (The Red)]

But slaves were in Madeira in the 1500s through the 1700s (after which they probably blended into the population) so I'd expect a diluted amount of West African to be present in the population since. I may be wrong, though.

There were also various Berber and Arab types along with Gaunches that worked the plantations. With Madeira, more than the Azores, you really need to closely examine the familial history of each participant to determine if a person is representative of the Portuguese population as a whole (mainland). From what I have seen, the large majority of Madeirans look no different than mainland Portuguese but there is a small minority with "recent" Black African, Berber / Arab / Gaunche ancestry - non indigenous Portuguese.

 

[oreo_cookie]

From what I have seen, the large majority of Madeirans look no different than mainland Portuguese but there is a small minority with "recent" Black African, Berber / Arab / Gaunche ancestry - non indigenous Portuguese.

I agree. I might make a separate Spain/Portugal thread on here but every time there is one, it seems to be killed by argument.

 

[Dorianfinder]

But slaves were in Madeira in the 1500s through the 1700s (after which they probably blended into the population) so I'd expect a diluted amount of West African to be present in the population since. I may be wrong, though.

The chances are greater that European men have relations with non-European women when there is a predominantly male population that are either sailors or soldiers. Also if the population is a port of destination where many types come and go with brothels being frequented on a regular basis. Also the more heterogeneous a population the less prohibitive inter-racial relations would have been.

 

[Cambrius (The Red)]

I agree. I might make a separate Spain/Portugal thread on here but every time there is one, it seems to be killed by argument.

Well, there are always odd characters on genetics and biological anthropology boards who get some strange pleasure from lying about Iberians. These persons are frustrated because science has shown quite well that Spaniards and Portuguese are very mainstream Western Europeans, in genotype and phenotype. Like many other forums, from time to time, Eupedia get's it share of people obsessed with slandering Iberians.