Mutation of the linker region of the polymerase gamma-1 (POLG1) gene associated with progressive external ophthalmoplegia and Parkinsonism.

Objective: To define the molecular basis of the autosomal dominant progressive external ophthalmoplegia and parkinsonism in a large family with a dominantly transmitted multiple mitochondrial DNA deletion disorder.

Design: Microsatellite analysis and screening of the progressive external ophthalmoplegia 1 (PEO1), adenine nucleotide translocator 1 (ANT1), and polymerase gamma-1 (POLG1) genes.

Results: We identified 3 novel heterozygous POLG1 substitutions in the same family.

Allelic variation of a functional polymorphism in the serotonin transporter gene and depression in Parkinson's disease.

A genetic susceptibility to depression in PD, acting via the serotonergic system, has been suggested. We examined the influence of allelic variation (L/S) in a functional polymorphism in the serotonin transporter (5-HTTLPR) gene upon mood in 108 PD patients and 82 controls. Using a logistic regression model we found no evidence for an association between 5-HTTLPR genotypes, or the presence of the S allele, and depression.

Mitochondrial DNA and survival after sepsis: a prospective study.

Background: Human genome evolution has been shaped by infectious disease. Although most genetic studies have focused on the immune system, recovery after sepsis is directly related to physiological reserve that is critically dependent on mitochondrial function. We investigated whether haplogroup H, the most common type of mitochondrial DNA (mtDNA) in Europe, contributes to the subtle genetic variation in survival after sepsis.

Mitochondrial DNA haplogroup cluster UKJT reduces the risk of PD.

There is increasing evidence that genetic variants of mitochondrial DNA have an important role in the cause of idiopathic Parkinson's disease. We determined the mitochondrial DNA haplogroup of 455 Parkinson's disease cases, 185 Alzheimer's disease cases, and 447 healthy English control subjects. The UKJT haplogroup cluster was associated with a 22% reduction in population-attributable risk for Parkinson's disease.