Blog

Saludos from the 17IHIW

by Monterey Bay, California.

One thing that usually surprises Europeans is how much bigotry and creationism are spread in this paradise of science and technique that the USA are supposed to be.

Looks like astrology or lovetalk but in an opposite mode, that is, we don’t really read and use horoscopes, but we talk as if the subject deserved some credit. I start to believe that it is a general feature of this country’s culture. Here I’ve seen a lot of talk about population genetics but then no use of it.

If a sample does not conform with Hardy-Weinberg expectations then the sample frequencies are at most sample frequencies and certainly not *population* frequencies. If a sample is in Hardy-Weinberg equilibrium then it makes no sense to say that the population is composed of two or three different sub-populations, as, if it was the case, the Wahlund effect would ensure deviation from Hardy-Weinberg expectations: you can’t have simultaneously two exclusive situations.

[Publication] CWD catalogue form EFI-PG is out

HLA journal (formerly Tissue Antigens) published the first article resulting from the collaborative effort of the EFI population genetics working group: an EFI labs based catalogue of Common and Well Documented alleles.
The study compares this new catalogue with the former ASHI, and identifies a number of alleles that are not commun in Europe and others that altough common in Europe were absent form ASHi’s catalogue.
The link for the paper is http://onlinelibrary.wiley.com/doi/10.1111/tan.12956/full and all comments are appreciated.

[Publication] Mapping the HLA diversity of the Iberian Peninsula

Mapping the HLA diversity of the Iberian Peninsula
Iñigo Romòn, Carmen Montes, Dario Ligeiro, Hélder Trindade, Alicia Sanchez-Mazas, José Manuel Nunes, Stéphane Buhler
Human Immunology 2016, 77 (10): 832-40

… These results outline the genetic landscape of the Iberian Peninsula, and confirm that the analysis of the HLA polymorphism may reveal relevant signatures of past demographic events even when data from donor registries are used. This conclusion stimulates future developments of the Spanish registry, presented here for the first time.

There are some really nice graphs in the paper.

[Publication] Joint divergent asymmetric selection

Immunogenetics. 2016; 68: 401–416.
Published online 2016 May 27. doi: 10.1007/s00251-016-0918-x

HLA class I molecular variation and peptide-binding properties suggest a model of joint divergent asymmetric selection

… We thus propose that HLA-A and HLA-B evolved through a model of joint divergent asymmetric selection conferring all populations an equivalent immune potential…

It is on open access: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4911380/
Enjoy.

EFI Population Genetics Working Group: Open meeting

Wednesday 11 May 201
Location: AEGLE B HALL

Population genetics at EFI
12:00: Alicia Sanchez-Mazas
Summary of current work, new objectives & challenges
12:10: Derek Middleton
Allelefrequencies.net
12:20: José Manuel Nunes
HLA-net

Ongoing HLA population studies
12:30: Thomas Goeury (Geneva)
From SSO to NGS in HLA population studies: the case of Mandenka
12:42: Iñigo Romón Alonso (Santander)
The HLA genetic landscape of the Iberian Peninsula
12:54: Sebastiaan Heidt (Leiden)
HLA population genetics in organ transplantation: EUROSTAM
13:06: Lisa Creary (Stanford)
HLA population Genetics in disease associations: schizophrenia

Questions & concluding remarks
13:20: Alicia Sanchez-Mazas

Eurostam final meeting and epitope workshop

The last meeting of EUROSTAM (A Europe-wide strategy to enhance transplantation of highly sensitized patients on basis of Acceptable HLA mismatches, http://eurostam.eu/) took place in Leiden from 18th to 20th of November 2015. It included a workshop on the current status of the definition of HLA epitopes and their clinical relevance.

The Pheno Search utility developed in Geneva as part of this project was presented at the Regentenkamer (see picture below). This tool allow to output HLA phenotypes frequencies in different European populations (including complex search expressions).

Eurostam_Leiden

HLA supertype variation across populations

The HLA-A and B supertype variation in worldwide populations was investigated in a recently published study by Francisco et al. (2015). Some functional differences between HLA-A and HLA-B were uncovered.

To learn more about these results : http://link.springer.com/article/10.1007/s00251-015-0875-9

Reference:
HLA supertype variation across populations: new insights into the role of natural selection in the evolution of HLA-A and HLA-B polymorphisms
Rodrigo dos Santos Francisco , Stéphane Buhler, José Manuel Nunes, Bárbara Domingues Bitarello, Gustavo Starvaggi França, Diogo Meyer, Alicia Sanchez-Mazas
Immunogenetics.