Charles Darwin's Mitochondria

Article excerpt

ABSTRACT Charles Darwin's long-term illness has been the subject of much speculation. His numerous symptoms have led to conclusions that his illness was essentially psychogenic in nature. These diagnoses have never been fully convincing, however, particularly in regard to the proposed underlying psychological background causes of the illness. Similarly, two proposed somatic causes of illness, Chagas disease and arsenic poisoning, lack credibility and appear inconsistent with the lifetime history of the illness. Other physical explanations are simply too incomplete to explain the range of symptoms. Here, a very different sort of explanation will be offered. We now know that mitochondrial mutations producing impaired mitochondrial function may result in a wide range of differing symptoms, including symptoms thought to be primarily psychological. Examination of Darwin's maternal family history supports the contention that his illness was mitochondrial in nature; his mother and one maternal uncle had strange illnesses and the youngest maternal sibling died of an infirmity with symptoms characteristic of mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS syndrome), a condition rooted in mitochondrial dysfunction. Darwin's own symptoms are described here and are in accord with the hypothesis that he had the mtDNA mutation commonly associated with the MELAS syndrome.

Charles Darwin (1809-1882) suffered a debilitating illness for most of his adult life with many very varied and bizarre symptoms. The nature of this illness has been the subject of much academic industry and more than 40 different diagnoses have been proposed at various times (Colp 2008). The illness was such that Darwin would be incapacitated for days, weeks at a time. Despite this, he produced an enormous and impressive volume of work, writing 19 books, numerous papers, and thousands of letters, many of which are preserved today (Darwin et al. 2009). Apart from his most famous work, On the Origin of Species . . ., Darwin's other publications, such as Variations in Domesticated Animals and Plants, published in two volumes, were works that represented years of study and experimentation.

Darwin never ascertained the genetic basis of hereditary, despite his interest in and work on the subject and his awareness that evolution depends on the existence of heritable variability within a species (Charlesworth and Charlesworth 2009). He carried out extensive plant breeding experiments in his garden and hothouse at Down House in Kent and meticulously recorded numbers of resulting varieties. He failed, however, to interpret these numbers as evidence of hereditable units (Howard 2009). Despite this failure to produce a convincing theory of heredity, he made the single most important contribution to our understanding of biology, his theory of evolution.

In this article, it is proposed that Darwin himself may have had an unusual heredity condition, a mitochondrial genetic disease. Several mitochondrial diseases show bizarre and variable symptoms and those of one in particular, the MELAS syndrome (Finsterer 2007), closely mirror those of Darwin's condition.

Charles Darwin's Illness

Charles Darwin suffered illness for most of his adult life with many very differing symptoms. Some of these symptoms were present when he was a university student, both in Edinburgh and Cambridge. In Edinburgh he was known to have a "weak stomach" and was unable to watch surgical operations; at Cambridge he suffered from eczema of his lips and hands. When attending two recitals in 1 day at a Birmingham Music Festival, he experienced extreme fatigue-"most terribly knocked up," as he expressed in his autobiography (Barlow 1958). When he was a resident in Plymouth, before he sailed on HMS Beagle, he experienced an episode of rapid heartbeat with "pain around the heart."

During his voyage on the Beagle, Darwin suffered greatly from seasickness. …