Diagnoses for Charles Darwin's Illness: A Wealth of Inaccurate Differential Diagnoses.

Charles Darwin suffered from a relapsing, debilitating illness for much of his adult life with numerous, differing symptoms. His occasional problems as a student, his seasickness throughout the voyage of the HMS Beagle, and his brief illnesses when ashore in South America and Australia were all early expressions of this illness. Diagnoses for Darwin's illness are as numerous as his symptoms and are equally variable. Many diagnoses reflect the medical fashion of their time; psychological and psychogenic diagnoses once flourished. These diagnoses have recently been comprehensively reviewed in an uncritical and unbiased account. Rather than a repeat review of diagnoses this paper aims to critique and make a critical appraisal of the diagnoses given. As stated, they are not all right. Some are not wrong but are simply incomplete. Pathological mitochondrial DNA (mtDNA) mutations are the cause of a variety of childhood diseases and more recently have been recognized as the cause of some adult-onset conditions with a plethora of presenting symptoms. The diagnosis favored here is that Darwin suffered from such a disorder due in his case to a maternally inherited pathological mtDNA mutation. This proposal should be seen in the context of self-certainty and subject to similar critical appraisal. Diagnosing Darwin may have a unique, correct solution, a solution that would benefit those who suffer from a similar disorder today and who, like Darwin, are misdiagnosed, misunderstood, and inappropriately treated.