LUKE Hartley's bone marrow transplant is shaping up to be a success.

If the Hampshire seven-year-old continues to improve at his current rate, his family will finally be able to put the life threatening X-linked lymphoproliferative (XLP) syndrome behind them.

Luke is still in isolation in London's Great Ormond Street Hospital, where he will spend Christmas, as he has a weakened immune system as he recovers from the transplant he had a month ago.

Father David Hartley, of Romsey, said: "Luke has 100 per cent donor engraftment, which means that the immune system that is emerging is all from the donor and his old faulty immune system is being replaced.

"It's wonderful news and we are just so pleased and relieved.

"Luke's blood counts are also getting better each day, showing that the new bone marrow is doing its job. Luke remains in wonderful spirits and wants to be entertained every waking hour."

This was the second bone marrow transplant Luke has undergone. The first attempt this summer involved his brother Nathan, 13, being the donor, but the transplant failed.

All four Hartley brothers were diagnosed with XLP, or Duncan's disease, in November 2003 and their parents were warned they were unlikely to live into their teenage years without a transplant.

Joshua, 15, Nathan, 13, and 11-year-old Daniel have already had successful transplants to cure them of the condition.

A bone marrow transplant is the only cure for the genetic condition, which leaves sufferers with no immunity against life threatening conditions such as glandular fever and cancer of the blood.