Europe will see its first genetically engineered patients using a groundbreaking gene-splicing therapy this year after regulators approved trials.

The biotech company Crispr Therapeutics is hoping to cure the disease beta thalassaemia, a devastating blood disorder which reduces the production of haemoglobin, the protein which carries oxygen to cells.

Without sufficient oxygen, sufferers can be left with bone deformities, severe anaemia, slow growth, fatigue and shortness of breath.

The disease is caused by a genetic mutation in the HBB gene, but scientists are confident that they can alter the body’s code to fix the problem and restore healthy levels of haemoglobin.

It will be the first human disease to be treated using the technology in the West. China has already begun similar trials, but does not have the same strict regulation as in Europe or the US. The company has yet to decide where the first trial will take place.

British experts said the trial marked the start of clinical gene therapy, and hailed the new treatments as "very promising".