Michael James Welsh is an Americanpulmonologist. He is the currentRoy J. Carver Chair in Biomedical Research,^[2] theProfessor ofInternal Medicine inPulmonary,Critical Care andOccupational Medicine at the Department of Internal Medicine, and the Director of Pappajohn Biomedical Institute,Roy J. and Lucille A. Carver College of Medicine,University of Iowa.^[3] He is also a professor at the Department ofNeurosurgery, Department ofNeurology, and Department of Molecular Physiology andBiophysics.^[3] He received the 2022Shaw Prize in Life science and Medicine, together withPaul A. Negulescu, for their work that uncovered the physiological defects incystic fibrosis and developed effectivemedications.^[4] He also received the 2025 Lasker Award.

Welsh was born and raised inMarshalltown,Iowa, and went toLoras College inDubuque.^[1] He obtained hisBSc from theUniversity of Iowa, then hisMD fromCollege of Medicine of the same university (now theRoy J. and Lucille A. Carver College of Medicine) in 1974.^[1][3] He completed hisresidency inInternal Medicine at theUniversity of Iowa Hospitals and Clinics,^[3] during which theattending physicians supervising him induced his interest in research.^[5]

After hisresidency, Welsh spent 2 years at theUniversity of California, San Francisco and thenUniversity of TexasMedical School at Houston as a research fellow, returning to theUniversity of Iowa in 1981 and becoming anassistant professor in the Department ofInternal Medicine, eventually promoted toProfessor of Internal Medicine and Professor of Molecular Physiology andBiophysics.^[1]

Welsh was the President of theAmerican Society for Clinical Investigation between 1996 and 1997,^[6] and has been the President of theAssociation of American Physicians.^[7] Currently, Welsh is an investigator at theHoward Hughes Medical Institute (since 1989)^[8] and sits on the Scientific Advisory Board of the Harrington Discovery Institute atUniversity Hospitals Cleveland Medical Center.^[7]

Welsh's research centered oncystic fibrosis, specifically theCFTR protein, anion channel that allowschloride ions to pass through. His studies helped answer questions about why defects in the protein emerge and how these defects affect the protein's function.^[9][10] In 1989,Lap-Chee Tsui,Francis Collins, and their team discovered thegene that encodes the CFTR protein and found that changes in the protein caused cystic fibrosis.^[11] Welsh's group discovered in 1991 that the CFTR protein is achloride channel, meaning it allows chloride ions to pass across thecell membrane.^[12] The same year, his group reported how the activity of the CFTR protein could be regulated.^[13] He later categorized the four classes of CFTRmutations that are still in use today in an expanded format.^[14] Crucially, Welsh and his group found that when the CFTR protein contains F508del mutation, the most common mutation in cystic fibrosis patients, it could be transported to thecell surface under low temperature but not at body temperature.^[15] His study also showed F508del-mutated CFTR protein can function properly if it reached cell surface,^[16] paving the way for cystic fibrosis therapies. In recent years, Welsh has developedanimal models of cystic fibrosis, most notably inpigs, allowing for the study of the disease in anin vivo setting.^[17]

• 1994 - James Burns Amberson Lecture,American Thoracic Society^[18]
• 1997 - Member of theNational Academy of Medicine^[19]
• 1998 - Member of theAmerican Academy of Arts and Sciences^[20]
• 2000 -Member of theNational Academy of Sciences^[21]
• 2009 - Gordon Wilson Medal,American Clinical and Climatological Association^[1]
• 2017 -Walter B. Cannon Award Lectureship,American Physiological Society^[22]
• 2017 -Steven C. Beering Award,Indiana UniversitySchool of Medicine^[23]
• 2018 -Warren Alpert Foundation Prize^[24]
• 2020 -George M. Kober Medal^[25][26]
• 2022 -Shaw Prize in Life Science & Medicine^[27]
• 2023 -Wiley Prize^[28]
• 2023 - Switzer Prize^[29]

• Living people
• Members of the United States National Academy of Sciences
• Howard Hughes Medical Investigators
• Members of the National Academy of Medicine
• University of Iowa faculty
• University of Iowa alumni
• American physicians

• Articles with short description
• Short description matches Wikidata
• Use American English from October 2022
• All Wikipedia articles written in American English
• Use mdy dates from October 2022
• Articles with hCards
• Year of birth missing (living people)