A MOTHER who is desperate to have a "designer baby" to save her son's life could have to wait another five years for test results.

Denise Kelly wants to have another child in a bid to save her four-year-old son Nathan Howarth who suffers from the rare genetic disorder fanconi anaemia.

However, Nathan's condition is so rare that tests being carried out to find which type of gene mutation his illness stems from could take another five years.

Miss Kelly, from Great Lever, eventually hopes to have pioneering treatment which would involve IVF embryos being screened to ensure her baby would be a genetic match to help Nathan.

Stem cells from her future baby's umbilical cord would then be manipulated to form healthy red blood cells to be infused into Nathan.

But as waiting lists in the country are so long she is likely to have to travel to the USA where there are dozens of clinics prepared to help parents wanting the treatment.

Miss Kelly's argument for travelling to America is even stronger following the controversial decision made last week by the Government body which refused a couple the chance to have the IVF "tissue-typing" treatment to save their seriously ill son.

The Human Fertilisation and Embryology Authority has banned Michelle and Jayson Whitaker from Bicester having a new baby screened in a bid to find the perfect tissue match to save their three-year-old son who suffers from a rare blood disorder called Diamond Blackfan Anaemia. Like Nathan's parents, the couple is now also hoping to pay for the treatment across the Atlantic. As fanconia anaemia is even more rare than Diamond Blackfan Anaemia, it means tests to find out the particular mutation of the illness are more painstaking as there are so many thousands of gene combinations which need to be investigated.

Miss Kelly and Mr Howarth, of Marion Street, have even been warned that Nathan's genetic make-up could result in an "unknown mutation" of the illness being found.

Until the test results come through the couple cannot take any further action to help their son. Miss Kelly said: "What happened to the couple from Oxford seems very unfair -- but they should go to America. Nathan's illness is so rare that there's probably nobody in this country who has the knowledge to help him." "It might take years to get Nathan's results, but time is of the essence for him and five years away might be too late," said Miss Kelly.

Fanconi anaemia affects white blood cells and the production of bone marrow. and people suffering from the illness have a life expectancy of about 12.