A team of international researchers have identified a new mutation in a gene called KCTD7, which causes progressive myoclonus epilepsy (PME). This discovery has important implications for genetic testing, and it may also lead to the design of new therapies for PME and other related conditions.PME is a group of conditions characterized by muscle jerks, seizures, lack of voluntary muscle coordination and reduced thinking ability. It is usually diagnosed in young children and may result in death or severe disability.Although scientists have already identified several genetic factors for PME, they have not been able to fully understand the exact mechanisms that cause the condition.In the present study, published in the scientific journal Brain, the team reports the case of two brothers from Saudi Arabia with PME. The first boy developed muscle jerks and uncoordinated muscle movements at the age of nine months. By the age of two he had lost the ability to walk and talk and he developed drug-resistant PME. His younger brother developed similar symptoms when he was six months old.The researchers genetically analysed both boys and their parents (who were first cousins) and found a new mutation in their KCTD7 genes. Both parents had one copy of the mutated gene and the boys inherited one copy from each parent. Having two copies of the mutated gene meant they developed the condition.In a press release, the senior author of the study, Dr Farrukh Abbas Chaudhry, said: “The identification of the mutations now allows us to offer this and other affected families pre-natal genetic testing…More research on KCTD7 and other related proteins may identify their involvement in other forms of epilepsy and/or other diseases.”The KCTD7 gene encodes for a protein that plays an important role in the responsiveness of neurons to external signals. The mutation causes the protein product of the gene to be shorter than normal and not to function properly. This results in neurons to become unstable and leads to PME by weakening the communication between neurons.Author: Dr Özge ÖzkayaClick here for more news articles about epilepsy in children.