While the heterozygous advantage is apparent for many autosomal recessive genetic diseases, the effects of having the actual disease can be devastating. Prenatal genetic testing is available to people in certain high -risk populations. Testing for Sickle Cell and Cystic Fibrosis are now commonplace, allowing many carriers to determine if there is a risk of passing along the gene. If only one parent carries the recessive trait, there is no danger of the children developing the genetic disease. If both parents are found to be carriers, genetic counseling may be advised for the family, so that fully informed decisions can be made, prior to any pregnancy occurring.
The subclade E3b1 (probably originating in eastern Africa) has a wide distribution in Sub-Saharan Africa, the Middle East, and Europe. This haplogroup, in Italy , is represented by E-M78, E-M123 and E-M81 (Figure 3)  and reaches a frequency of 8% in northern and central Italy and slightly higher, 11%, in the south of that country. 
It has also been argued that the European distribution of E3b1 is compatible with the Neolithic demic diffusion of agriculture; thus, two subclades—E3b1a- M78 and E3b1c- M123 —present a higher occurrence in Anatolia , the Balkans , and the Italian peninsula . Another subclade, E3b1b- M81 is associated with Berber populations and is commonly found in regions that have had historical gene flow with northern Africa, such as the Iberian Peninsula , the Canary Islands , and Sicily .