Direct-to-consumer genetic tests were called into question by the US authorities last week.

An undercover investigation by the US Government Accountability Office (GAO) found that test results were often inaccurate and misleading.

Gregory Kutz, a special investigator at the GAO, told ABC News that: 'Consumers need to know that today, genetic testing for certain diseases appears to be more of an art than a science'.

The investigators looked at genetic tests from four companies, which included 23andMe, deCODE Genetics, Navigenics and Pathway Genomics.

The findings were presented to a Congressional Committee last Wednesday, 22 July, and have led to calls for tighter regulation.

Reporting to the Committee, Professor James Evans, a geneticist at the University of North Carolina said: 'The value of the bulk of this information is extremely low'.

A US Food and Drug Administration (FDA) spokesperson, Dr Jeffery Shuren, told ABC News that they were planning to ramp up the regulation of genetic testing companies.

However, Ashley Gould, a lawyer for 23andMe argued that: 'People have the right to access their genetic information. If they want to do that'.