De novo gene mutation causes Sunna´s disease

Sunna with her brother Viktor
Sunna and Viktor

De novo mutation in a gene, ATP1A3, causes the disease for two thirds of all AHC patients. This is the case for Sunna Valdis Sigurdardóttir who is the only one diagnosed with the disease here in Iceland. AHC stands for Alternating Hemiplegia of Childhood. Ever since the disease was recognized forty years ago it´s cause has been a mystery.
„This is the biggest news since the recognision of the disease“ says Sigurður Hólmar Jóhannesson, Air Traffic Controller. He and his wife, Ragnheiður Erla Hjaltadóttir a Flight Attendant for Icelandair, told their story in Fréttatiminn in May when they reveiled that they were expecting big news regarding AHC.
Last week there was a publication on the gene discovery in the science journal National Genetics and The Lancet. Scientists are optimistic that they will have a cure for the disease within the next 15 years if funding allows. Only 600-800 diagnosed patients have AHC in the whole world.
Sigurður says that although they now know which gene causes the disease for Sunna there are mixed feelings knowing it is the ATP1A3 since most of the individuals with this gene mutation develop a severe form of epilepsy that they fear. This form of epilepsy causes much trauma and can be terminal. Also knowing that it can take 15 years to find a cure is a lot to digest when each month can count.
„If we can find a drug that is already on the market and can counter affect the mutation then we can perhaps have a cure within 5 years and that would be the dream solution“ he says. „But if we need to develop a new drug specifically for AHC then the process can take up to 15 years from present until the drug is marketable. The cost of developing a new drug could be 100 million usd and that would be insurmountable.“
Sunna is six years old. She was born on February 9th 2006. She learned to walk fifteen month old and can go around on her own two feet but is unstable at times and has low muscle tone. Her mental development is that of a 2-3 year old and her speech that of a 1-2 year old. She can poorly tolerate bright lights, anxiety, stress, noice, being tired and crowds of people. All these elements and more can make her have an episode.
Sigurður says that Sunna´s well-being since the interview in May has been reasonable. She is having 2 episodes on averidge each week and at best she had 15 days without epsides this summer.
It was a team of scientists from the University of Duke that found the mutation with the support of ENRAH, AHC Foundation of USA, AHC association of Italy, Ireland, the Netherlands and France.

Gunnhildur Arna Gunnarsdottir
Translated by Sigurður H. Jóhannesson