Carrier screening for Beta-thalassaemia: a review of international practice

Abstract

b-thalassaemia is one of the most common single-gene inherited conditions in the world, and thalassaemia carrier screening is the most widely performed genetic screening test, occurring in many different countries. b-thalassaemia carrier screening programmes provide a unique opportunity to compare the delivery of carrier screening programmes carried out in different cultural, religious and social contexts. This review compares the key characteristics of b-thalassaemia carrier screening programmes implemented in countries across the world so that the differences and similarities between the programmes can be assessed. The manner in which thalassaemia carrier screening programmes are structured among different populations varies greatly in several aspects, including whether the programmes are mandatory or voluntary, the education and counselling provided and whether screening is offered pre-pregnancy or antenatally. National and international guidelines make recommendations on the most appropriate ways in which genetic carrier screening programmes should be conducted; however, these recommendations are not followed in many programmes. We discuss the implications for the ethical and acceptable implementation of population carrier screening and identify a paucity of research into the outcomes of thalassaemia screening programmes, despite the fact that thalassaemia screening is so commonly conducted.

Carrier screening in preconception consultation in primary care

“…A recent review of international practice of betathalassaemia carrier screening described a wide variety of programs in different countries that might be mandatory or voluntary, preconceptional or prenatal, and involve a broad range of education and counselling practices (Cousens et al 2010). Typically, preconceptional carrier screening is voluntary when it occurs in high schools and more often mandatory when applying for a marriage license (described as pre-marital screening) (Cousens et al 2010).…”

“…Typically, preconceptional carrier screening is voluntary when it occurs in high schools and more often mandatory when applying for a marriage license (described as pre-marital screening) (Cousens et al 2010). These seem to be acceptable to the communities in which these approaches exist such as in Bahrain (Al Arrayed and Al Hajeri 2010) or in Malaysia where these might be implemented (Wong et al 2011a(Wong et al , 2011b.…”

“He didn’t say that thalassaemia might come up” — β-thalassaemia carriers’ experiences and attitudes

“…Thus, population carrier screening in Australia for genetic conditions such as cystic fibrosis and Tay-Sachs disease is usually offered through formal, coordinated programs (Gason et al 2003;Massie et al 2009). No such program exists for thalassaemia carrier screening (Cousens et al 2010).…”

Prevention of sickle cell disease: observations on females with the sickle cell trait from the Manchester project, Jamaica

“…In transfusion-dependent beta thalassaemia, where survival requires blood transfusion every 3-4 weeks from early life and regular chelation, there is a powerful stimulus to avoid such births (Cousens et al 2010). The clinical picture is totally different in families at risk of a baby with SS disease, where the outcome varies from death in the first year of life to survival to the age of 80 years and a median survival in Jamaica of 55 years (Wierenga et al 2001).…”