European Journal of Human Genetics (2005) 13, 748–752. doi:10.1038/sj.ejhg.5201425 Published online 13 April 2005

Mitochondrial DNA haplogroup K is associated with a lower risk of Parkinson's disease in Italians

Daniele Ghezzi1,13, Cecilia Marelli2,12,13, Alessandro Achilli3, Stefano Goldwurm4, Gianni Pezzoli4, Paolo Barone5, Maria Teresa Pellecchia5, Paolo Stanzione6, Livia Brusa6, Anna Rita Bentivoglio7, Ubaldo Bonuccelli8, Lucia Petrozzi8, Giovanni Abbruzzese9, Roberta Marchese9, Pietro Cortelli10, Daniela Grimaldi10, Paolo Martinelli11, Carlo Ferrarese12, Barbara Garavaglia1, Simonetta Sangiorgi11, Valerio Carelli11, Antonio Torroni3, Alberto Albanese2 and Massimo Zeviani1

  1. 1Unit of Molecular Neurogenetics, National Neurological Institute, 'Carlo Besta', Milan, Italy
  2. 2First Division of Neurology, National Neurological Institute 'Carlo Besta', Milan, Italy
  3. 3Department of Genetics and Microbiology, University of Pavia, Italy
  4. 4Centro Parkinson, Istituti Clinici di Perfezionamento, Milan, Italy
  5. 5Department of Neurological Sciences, University 'Federico II', Naples, Italy
  6. 6Neurological Clinics, University of Tor Vergata, Rome, Italy
  7. 7Institute of Neurology, Catholic University, Rome, Italy
  8. 8Neurological Clinics, University of Pisa, Italy
  9. 9Department of Neurosciences, Ophthalmology and Genetics, University of Genoa, Italy
  10. 10Neurological Clinics, University of Modena, Italy
  11. 11Department of Neurological Sciences, University of Bologna, Bologna, Italy
  12. 12Institute of Clinical Neurology, University of Milan-Bicocca, Milan, Italy

Correspondence: Dr M Zeviani, Unit of Molecular Neurogenetics, National Neurological Institute 'Carlo Besta', via Temolo 4, Milan 20126, Italy. Tel: +39 02 23942630; Fax: +39 02 23942619; E-mail:

13These authors contributed equally to the work.

Received 4 January 2005; Revised 11 March 2005; Accepted 16 March 2005; Published online 13 April 2005.



It has been proposed that European mitochondrial DNA (mtDNA) haplogroups J and K, and their shared 10398G single-nucleotide polymorphism (SNP) in the ND3 gene, are protective from Parkinson's disease (PD). We evaluated the distribution of the different mtDNA haplogroups in a large cohort of 620 Italian patients with adult-onset (>50, <65 years of age) idiopathic PD vs two groups of ethnic-matched controls. Neither the frequencies of haplogroup J nor that of 10398G were significantly different. However, the frequency of haplogroup K was significantly lower in PD. Stratification by sex and age indicated that the difference in the distribution of haplogroup K was more prominent in >50year old males. In spite of the common 10398G SNP, haplogroups J and K belong to widely diverging mitochondrial clades, a consideration that may explain the different results obtained for the two haplogroups in our cohorts. Our study suggests that haplogroup K might confer a lower risk for PD in Italians, corroborating the idea that the mitochondrial oxidative phosphorylation pathway is involved in the susceptibility to idiopathic PD.


mitochondrial DNA haplogroups, Parkinson's disease, single nucleotide polymorphism