Increased prevalence of two mitochondrial DNA polymorphisms in functional disease: Are we describing different parts of an energy-depleted elephant?
About 20% of the population suffers from "functional syndromes". Since these syndromes overlap greatly in terms of co-morbidity, pathophysiology (including aberrant autonomic activity) and treatment responses, common predisposing genetic factors have been postulated. We had previously showed that two common mitochondrial DNA (mtDNA) polymorphisms at positions 16519 and 3010 are statistically associated with the functional syndromes of migraine, cyclic vomiting syndrome and non-specific abdominal pain. Herein, among individuals with mtDNA haplogroup H (HgH), the presence of these two mtDNA polymorphisms were ascertained in additional functional syndromes: chronic fatigue syndrome, complex regional pain syndrome, sudden infant death syndrome, and major depressive disorder. Polymorphic prevalence rates were compared between disease and control groups, and within each disease group in participants with and without specific clinical findings. In all four conditions, one or both of the polymorphisms was significantly associated with the respective condition and/or co-morbid functional symptomatology. Thus, we conclude that these two mtDNA polymorphisms likely modify risk for the development of multiple functional syndromes, likely constituting a proportion of the postulated common genetic factor, at least among individuals with HgH. Pathophysiology likely involves broad effects on the autonomic nervous system.
Division of Medical Genetics and the Saban Research Institute, Children's Hospital Los Angeles, CA USA; Department of Pediatrics, Keck School of Medicine at the University of Southern California, Los Angeles, CA USA. Electronic address: richard.boles@courtagen.com.
Richard G
RG
Boles
Division of Medical Genetics and the Saban Research Institute, Children's Hospital Los Angeles, CA USA.
Essam A
EA
Zaki
Division of Clinical Sciences, St. George's University of London, Cranmer Terrace, London United Kingdom.
Jonathan R
JR
Kerr
Division of Medical Genetics and the Saban Research Institute, Children's Hospital Los Angeles, CA USA.
Kingshuk
K
Das
Division of Medical Genetics and the Saban Research Institute, Children's Hospital Los Angeles, CA USA.
Sawona
S
Biswas
Department of Clinical Neuroscience, Division of Psychiatry, Karolinska Institutet, Stockholm Sweden.
Ann
A
Gardner
D000293:Adolescent; D000328:Adult; D000368:Aged; D020918:Complex Regional Pain Syndromes / Q000235:genetics*; D004272:DNA, Mitochondrial / Q000235:genetics*; D003865:Major Depressive Disorder / Q000235:genetics*; D015673:Fatigue Syndrome, Chronic / Q000235:genetics*; D005787:Gene Frequency; D056726:Genetic Association Studies; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008875:Middle Aged; D011110:Polymorphism, Genetic; D015995:Prevalence; D013398:Sudden Infant Death / Q000235:genetics*; D055815:Young Adult
D004272:DNA, Mitochondrial
16519T>C; 3010G>A; Chronic pain; Dysautonomia; Psychosomatic; Sudden infant death syndrome SIDS