NEW YORK (GenomeWeb News) – A majority of clinical geneticists in Europe are concerned that genetic tests marketed directly to consumers are not clinically useful, and a large percentage believe that sales of certain types of DTC tests should be more closely regulated or banned, according to a study presented today at the European Society of Human Genetics conference in Amsterdam.
A survey of 131 clinical geneticists in Europe found that 90 percent of respondents felt that DTC tests for predictive disease risks based on genes should require face-to-face medical supervision.
For tests for mutations with a high rate of penetrance, where 50 or 60 percent or more of the individuals with the mutation will exhibit symptoms, 93 percent of the geneticists said they should require such direct supervision. Nearly four in five, 79 percent, of the geneticists also said that carrier testing for homozygous monogenic disorders, such as sickle cell anemia, should require medical supervision.
"Clinical geneticists' concerns with DTC genetic tests are mostly related to the fact that these tests usually lack clinical validity and utility," Heidi Howard, one of the study's investigators and a researcher at the University of Leuven, said in a statement.
"Moreover, these tests are usually carried out without the provision of genetic counseling. According to the experiences of clinical geneticists, patients often do not know how to interpret the results they receive and are often confused by them. However, almost all clinical geneticists feel that they have a duty to provide counseling if patients contact them after having purchased a DTC genetic test," Howard said.
Of the geneticists surveyed, 69 percent thought that DTC genetic tests for prenatal gender should be banned, 63 percent wanted to ban DTC genome scans, and 53 percent believe that preconception disease carrier tests also should be banned. DTC ancestry testing caused far less concern among the group, with only 27 percent preferring such offerings be banned.
The researchers found that 44 percent of the clinical geneticists it surveyed had been contacted by patients who had taken DTC genetic tests, and 98 percent of those respondents said that they had discussed those results with these patients.
"Better regulation is needed at the level of market introduction of these tests", added University of Leuven professor and co-investigator Pascal Borry. "As in the case of drugs, a procedure should be developed for genetic tests."