disease in focus

Estimated to affect more than 400 million people around the world, diabetes is one of the most common chronic disorders, with a range of different types – including a mitochondrial disease that manifests as diabetes. Maternally inherited diabetes and deafness, or MIDD, was identified as a specific condition in the early 1990s, after a team of scientists examined reports suggesting an increased incidence of some forms of diabetes being transmitted from mother to child.

Mitochondrial diseases are a clinically, biochemically and genetically heterogeneous group of disorders. Signs, symptoms and the organs involved can differ from one person to another, making the diagnosis of mitochondrial diseases and the search for potential therapies complex. Here we outline the heterogeneity surrounding mitochondrial diseases and explore some of the challenges biopharma companies active in this field, including Khondrion, face in developing much needed treatments for patients.

Simple functions such as blinking and breathing are actions that we take for granted. However, for those living with Leigh disease, these normally subconscious body functions can become difficult or even impossible to execute at all. First described in the 1950s by Denis Leigh, a British neuropsychiatrist, Leigh disease is a rare inborn error of metabolism, importantly touching the brain, that affects approximately 1 in 40,000 newborns, with quickly progressing symptoms frequently starting in the first year of life.

Cognition is an important function of the brain so we can gain knowledge and understanding. These mental processes include thinking, knowing, remembering, judging, planning, understanding and responding to information and problem-solving. They are vital for our everyday functions – whether that’s getting ready for work, remembering where we left our house keys, reminiscing about times from our past or planning a holiday in the future.

Classic MELAS Syndrome (Mitochondrial encephalopathy with lactic acidosis and stroke-like episodes), MIDD (maternally inherited diabetes mellitus and deafness) and Mixed Phenotypes all belong to a clinical spectrum of mitochondrial diseases most frequently caused by a mutation, the m.3243A>G PMD mutation, in the MT-TL1 gene in the mitochondrial DNA (mtDNA). Most DNA, called nuclear DNA, is situated in chromosomes within the nucleus of a cell.  Mitochondria however, which are found within all cells of the human body, except red blood cells, and are responsible for producing energy necessary for life, also contain small copies of their own DNA known as mitochondrial DNA. In this first of a series of forthcoming mitochondrial disease spotlights we focus on Classic MELAS Syndrome.

Movement, the act or process of moving, the change of place or position or posture, is a complex process under the control of many different parts of the central nervous system including the brain (frontal cortex, basal ganglia, cerebellum) and spinal cord. As brain involvement is common in all ages of primary mitochondrial disease, many patients with mitochondrial disease encounter movement difficulties, described in medical literature as ‘movement disorders’. Here, we briefly touch upon the movement disorders in children with mitochondrial disease, which have a huge impact on quality of life.