Bureaucracy is partly to blame for the difficulty in creating a free national screening programme for the genetic disorders most prevalent among Jews, the JC understands.

A number of agencies, including the Department of Health and NHS England, are said to have been unwilling to take responsibility for funding and organising wider screening for the Jewish community.

Public Health England, an executive agency of the Department of Health, also works on issues relating to screening, co-ordinating its efforts with the National Screening Committee (NSC).

But there is confusion within the agencies over which group is ultimately responsible for commissioning and funding a full national programme for the disorders covered by Jnetics.

A Department of Health spokesperson told the JC on Wednesday: "Genetic testing on the NHS is conducted according to the advice of experts, including those on the UK Genetic Testing Network and the UK National Screening Committee." Jnetics is funded by private donors within the community, including small contributions from fundraising events, and with grants from charitable trusts. It receives no government money.

Clearly we would like the NHS to commission an expanded test

People wishing to be screened pay £190 to Jnetics towards the cost, which is around £250 per participant. Ashkenazi Jews living in London can be tested for Tay-Sachs free on the NHS, with those outside London able to request the test through their GP. There is no guarantee of receiving it.

There are differing estimates of the cost of providing screening for all those who require it. One calculation is that to test around 2,500 people every year - and to provide the education programme that accompanies screening - would cost in the region of £700,000.

But Jnetics also estimates that to launch a full community programme would cost around £1.3 million over three years. The cost of care for children affected by the disorders covered by the charity, and for associated counselling, is considerably higher.

In Barnet, the local authority with the country's largest Jewish population, the clinical commissioning group (CCG) has supported Jnetics and provided money towards its work.

However, it is understood that the CCG requires a recommendation from the NSC to provide more money and the NSC is thought to be unable or unwilling to provide such advice because it is a national group and the CCG is local.

"Clearly we would like the NHS to commission an expanded test across the wider range of conditions," said Joey Ziff, Jnetics' assistant director.

The charity has been working with the Board of Deputies and the Jewish Leadership Council in an attempt to co-ordinate efforts on approaching the government.

"We are all in agreement that something needs to be done and we need a joint approach," Dr Ziff said.