Multiple Sclerosis in Parsis: A Historical Issue

I enthusiastically studied Parviz et al. article (1). It was an exceptional description of the possibility that great Persian and Andalusian physicians like Haly Abbas and Ibn Rushd might be familiar with optic neuritis and its relationship with paresthesia. This has not only been significant in medical history and proves the role of Persian traditional medicine in promoting science but also presents the hypothesis that in the old Persia, multiple sclerosis (MS) (the two common symptoms of which are optic neuritis and paresthesia) was probably prevalent to the extent that physicians were familiar with these cases and even described them. The author of the present study is aware that this is a big claim and proving it would need more precise review and inspection of Persian traditional medical texts which should be scrutinized by medical history researchers. Author of the present study decided to provide other relevant evidences including the prevalence of MS in a group of Iranian immigrants known as Parsis. Parsis of India are Zoroastrian Iranians that immigrated to India over 1000 years ago and are still living there (2). It is the fact that in recent years exogamies have become common and the youth marry followers of other religions; however, they are still considered in a single genetic package. In other words, Parsis of India might be exclusive samples for studying genetic status of ancient Per-sians due to being a minority and their cultural and religious attachments with Iran. It should be considered that conditions of Zoroastrians are different from other minorities like Jews or Assyr-ians. In terms of origin, Iranian Jews immigrated to Iran at the time of the Great Cyrus and after the release of Jerusalem (3) and Assyrians had their specific native land (4). Although other minorities like Armenians and Mandaeans are thought to be culturally Iranians, their genetic roots are different (5, 6). However, Iranian and Indian Parsi Zoroastrians are excluded. In fact, they are only different from Muslim Iranians in their religion. It should be mentioned that Muslim Iranians were previously Zoroastrians (7) and then converted to Islam; so Parsis are not genetically different from other Iranians. The only difference is genetic mixing of Muslim Iranians due to more exogenous cultural and genetic marriages than the Zoroastrians. Consequently, if we mean to know about our genetic roots and initial genetic mapping of the Irani-ans, these Parsis should be studied. As mentioned earlier, …