Biologist Elena Beristain found that few of the mutations found in BRCA1 and BRCA2 could be clearly identified as pathological. The fact is that the mutations found were numerous; their variation even depending on the population.
Beristain has been investigating the CAPV-EAE population.
She took 521 patients mainly from the Txagorritxu hospital in the Basque capital city of Vitoria-Gasteiz, and the Cruces hospital in Barakaldo, near Bilbao: 274 patients with breast or ovarian cancer, 115 family relations of these, and another 132 women who acted as a control population.
Beristain molecularly characterised the BCRA1 y BCRA2 genes of these individuals; apart from the exon 10 of the CHEK2 gene, also associated with the illness. Her thesis was defended at the University of the Basque Country (UPV/EHU) and it is entitled, Genetic study amongst women resident in the CAPV-EAE with hereditary breast/ovary cancer.
According to the results shown, different types of variations in the genes under study have been found, including pathological ones, neutral ones and those of uncertain significance.
Beristain stressed that, amongst those sporadic cases of under-40s, that is a especially rare condition: only in one case was a pathological mutation found.
The study also showed that for family-member carriers of mutation in the main genes under study, the accumulated risk of suffering breast cancer at 70 is 69 percent for the BRCA1 and 67 percent for the BRCA2.
This indicates that penetration is not complete and there exists the possibility that this gene does not, in the end, express itself.
She concludes that many of the mutations found in the CAPV-EAE are different from those described for other populations. However, she explains, amongst these, no founder effect mutation was found, i.e. there has been no case of some, many or all Basque patients coming from a small population of individuals having transmitted this common genetic characteristic to all their descendents.
However it may be, the new types of mutations found represent a contribution to the already existing variability. (ANI)