Correspondence

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Sheridan E, Wright J, Small N, et al. Risk factors for congenital anomaly in a multiethnic birth cohort: an analysis of the Born in Bradford study. Lancet 2013; 382: 1350–59. European Surveillance of Congenital Anomalies (EUROCAT). Prevalence tables. http://www.eurocat-network.eu/ accessprevalencedata/prevalencetables (accessed Dec 9, 2013). Smith LC, Budd JS, Field DJ, Draper ES. Socioeconomic inequalities in outcome of pregnancy and neonatal mortality associated with congenital anomalies: population based study. BMJ 2011; 343: d4306.

The study by Eamonn Sheridan and colleagues1 provides important prev a l ence data for congenital anomalies attributable to consanguinity and genotypic variation. We support the view of Alan Bittles2 that personalised genetic counselling should be offered to consanguineous couples to enable them to make informed decisions about family planning. However, our present knowledge of genetic disorders poses an important limitation; we do not know the proportion of genetic variants that cause congenital anomalies and that can be detected unequivocally in the carrier state. How much could such an approach help couples cut their risk of having an affected pregnancy? The proportion of couples at risk of recessive variants is unknown, and the number of variants of uncertain clinical significance will be substantial. We believe a large clinical pilot study should be initiated, in which consanguineous couples are recruited for systematic exome sequencing followed by genetic counselling, to assess feasibility and clinical usefulness of a screening approach in real-life situations. Community-based prevention strategies of haemoglobinopathies, including carrier screening and genetic counselling, were acceptable in many cultural settings and led to substantial falls in the number of affected individuals.3,4 Genetic counselling should remain neutral, and decisions should be voluntary. Screening should be accessible to all people who need it, but should not target characteristics to screen for on the basis of specific value commitments.5 Similar to existing www.thelancet.com Vol 383 January 11, 2014

programmes targeting known genetic variants in specific populations, this pilot study would support familyplanning goals of screened individuals rather than thwarting them. We declare that we have no conflicts of interest.

Periklis Makrythanasis, Hanan Hamamy, Stylianos E Antonarakis, Alex Mauron, *Samia A Hurst [email protected] Department of Genetic Medicine and Development (PM, HH, SEA); and Institute for Biomedical Ethics University of Geneva Medical School, 1211 Geneva, Switzerland (AM, SAH) 1

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Sheridan E, Wright J, Small N, et al. Risk factors for congenital anomaly in a multiethnic birth cohort: an analysis of the Born in Bradford study. Lancet 2013; 382: 1350–59. Bittles AH. Consanguineous marriages and congenital anomalies. Lancet 2013; 382: 1316–17. Angastiniotis MA, Hadjiminas MG. Prevention of thalassaemia in Cyprus. Lancet 1981; 317: 369–71. Hamamy HA, Al-Allawi NA. Epidemiological profile of common haemoglobinopathies in Arab countries. J Community Genet 2013; 4: 147–67. Wikler D. Can we learn from eugenics? J Med Ethics 1999; 25: 183–94.

Authors’ reply Ester Garne and Joan Morris are correct that the Born in Bradford birth cohort data for congenital anomalies do not include pregnancies that terminated before 28 weeks: the data we report refer to liveborn and stillborn infants only.1 We reported a protective effect of education on anomaly rates but we did not propose any theory to account for the finding because we had no further data that related to this observation. The size of the effect was the same in both Pakistani and white British mothers. In the study by Smith and colleagues,2 referred to by Garne and Morris, rates of termination are presented for nine selected anomaly types; unlike our report, it is not a comprehensive discussion of the rate of termination for all fetal anomalies. We acknowledge the suggestion by Garne and Morris that women with higher levels of education might be more likely to undergo a termination for a fetal anomaly, but

we do not have any data available to comment on it in the context of the Born in Bradford study. We agree completely with Periklis Makrythanasis and colleagues that the policy suggested in our report—to provide advice about anomaly risks to communities at increased risk—is untested, although evidence suggests that UK-based communities at risk would support such a policy.3,4 We endorse fully their proposal for a clinical pilot study for systematic exome sequencing of consanguineous couples, and we are attempting to gain funding for just such a study at present. We declare that we have no conflicts of interest.

*Eamonn Sheridan, John Wright, Peter Corry, Sam Oddie, Neil Small, Roger C Parslow [email protected] Bradford Institute for Health Research, Bradford Royal Infirmary, Bradford, BD9 6RJ, UK (ES, JW, PC, SO); School of Health Studies, University of Bradford, Bradford, UK (NS); Leeds Institute of Genetics, Health and Therapeutics, University of Leeds, Leeds, UK (RCP); and Section of Genetics, St James’s University Hospital, Leeds, UK (ES) 1

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Sheridan E, Wright J, Small N, et al. Risk factors for congenital anomaly in a multiethnic birth cohort: an analysis of the Born in Bradford study. Lancet 2013; 382: 1350–59. Smith LC, Budd JS, Field DJ, Draper ES. Socioeconomic inequalities in outcome of pregnancy and neonatal mortality associated with congenital anomalies: population based study. BMJ 2011; 343: d4306. Darr A, Small N, Ahmed WIU, et al. Examining the family-centred approach to genetic testing and counselling among UK Pakistanis: a community perspective. J Community Genet 2013; 4: 49–57. Ahmed S, Ahmed M, Sharif SM, Sheridan E, Taylor GR. Attitudes towards prenatal testing and termination of pregnancy in British Pakistani parents and relatives of children with recessive conditions in the UK. Prenat Diagn 2012; 32: 954–59.

Immigration and pregnancy in the UK We welcome The Lancet’s concerns (Nov 2, p 1459)1 about the health consequences of planned changes to immigration law in the UK, the lack of supporting evidence of so-called health tourism, and likely burdensome implementation costs. Without

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Analysis of the Born in Bradford birth cohort.

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