An area in Northern Ireland has been identified as a "giant hotspot" by scientists studying a gene defect which causes people to grow abnormally tall.
One in 150 people in Mid-Ulster were found to carry the gene, compared to one in 1,000 in Belfast and one in 2,000 in the rest of the UK.
More than three-quarters of carriers will never develop health issues, but it can cause long-term problems and be potentially life-threatening for those that do.
Scientists hope the work will help find those at risk of passing on the gene.
The gene - called AIP, but known as the "giant gene" - can result in too much growth hormone, which is produced and released by the pituitary gland, a pea-sized gland just below the brain.
The excessive production occurs as the result of a non-cancerous tumour in the gland.-read more and see video