Houston, John (1802–45), surgeon and anatomist, was born in the north of Ireland, probably at Ballindrait, Co. Donegal, son of James Houston, presbyterian minister at Ballindrait, and his wife Jane, daughter of the Rev. James Taylor of Convoy, Co. Donegal, and sister of Joseph Taylor, physician to the forces. There is no evidence of his schooling, but Joseph Taylor, who may have married a relative of his sister's husband, undertook to educate his nephew for the medical profession. On 13 January 1819 Houston was apprenticed to John Shekleton (1795–1824), who laid the foundations of the anatomical museum in the RCSI, and whose standing in the profession was very high. Shekleton made it possible for Houston to complete his medical studies in the RCSI after his uncle died around 1822, and the two young men became close friends. Unhappily, Houston's final examinations for his licentiate took place on the very day in May 1824 that he followed the coffin of his benefactor to his grave: Shekleton died from the effects of a dissecting wound. Houston, after successfully competing in a public examination, succeeded Shekleton (1 November 1824) as demonstrator in anatomy and as conservator of the anatomical museum, holding the latter position until 1841. His expertise and thoroughness as an anatomist, as well as his surgical skills, were remarked on by contemporaries. He published two catalogues of the normal and abnormal animal structures in the collection, and was granted £150 by the college. Graduating MD from Edinburgh in 1826, he was elected MRIA in 1829. He had a private practice in York St., helped found the City of Dublin Hospital as a teaching hospital for the RCSI, and was elected lecturer in surgery there in 1832; he was also a lecturer in surgery in the Park St. school of medicine from 1837.
His 1843 catalogue of the important Park St. anatomical collection made it more widely known, and Houston also published many valuable contributions on anatomy and pathology in the City of Dublin hospital reports and in other periodicals. He studied animal anatomy, having access to the bodies of animals that died in Dublin zoo, and also made a significant contribution to the understanding of the mechanism of the chameleon's tongue; he realised that erectile tissue played a role. His paper on the circulation of diving animals was also regarded as useful. In 1830 Houston described permanent folds or valves in the lining of the rectum; these were afterwards known as the ‘fold of Houston’. His name is also associated with a research scholarship tenable in the RCSI, which was inaugurated in 1958 to honour Houston's contributions to Irish medicine. He was the first person in Ireland to use the microscope in medicine, and the first to use the newly developed theories of the cell in the human organism to try to diagnose or explain disease, particularly various kinds of cancer. His pioneering work was reported to colleagues in the Surgical Society of Ireland in 1844; he suggested that the microscope could be used to study tumour cells to detect malignancy and to gauge how far a cancer had progressed.
Unfortunately, only a few months later (April 1845) Houston collapsed during a lecture in the hospital, and died 30 July 1845 in Dalkey, Co. Dublin, probably as a result of a cerebral haemorrhage. Biographical sources do not mention a marriage, though in 1833 a licence was issued in Dublin for the marriage of a John Houston to Thomason Turner; another was issued in 1841 for the marriage of a John Houston to Margaret Carmichael, who was perhaps a relative of the surgeon Richard Carmichael (qv). A portrait of Houston was presented to the RCSI.