A team of researchers from Liege University Hospital and from the National Institute of Health in Washington, led by Belgian professor Albert Beckers, have discovered the physical explanation for the most excessive cases of gigantism. The findings of their study were published in an article in the New England Journal of Medicine on Wednesday. The scientists have basically shown the mechanism affecting people who start growing abnormally fast very early on (before the age of 3). They look normal at birth, and then start developing too fast after a few months. The study considered, amongst others, the cases of a 3-year-old girl already 120cm tall and a “6-year-old boy taller than most 18-year-olds”, according to Albert Beckers.
These people are in fact suffering from a pituitary tumour producing an excess of growth hormones from a young age, explains the head of Endocrinology at Liege University Hospital. As they grow older they become the tallest giants in the world. A similar pituitary tumour can appear later in life, when bones cannot grow anymore, but in those cases different symptoms affect patients, such as huge hands and feet and disfigurement; this is termed acromegaly.
As for “real” giants, “we have discovered the root of their problem”, explains Albert Beckers.”It is a gene located on the X chromosome: it is called gene GPR101. Part of chromosome Xq26.3 is duplicated, and during these micro-duplications an overexpression of gene GPR101 can be observed.”
The breakthrough of the research team is that the overexpression of gene GPR101 in a pituitary tumour is the cause of the excessive secretion of growth hormones in young children suffering from gigantism.