Michael Terrence Gabbett is an Australian clinical geneticist and academic. He holds academic titles at a number of universities in South East Queensland.^[1][2] Gabbett is known for contributing to discovering the genetic basis of semi-identical (sesquizygotic) twins^[3][4][5][6] and defining the clinical features and molecular cause of Temple-Baraitser syndrome.^[7][8][9]

Gabbett attended high school at Marist College Ashgrove,^[10] where he was awarded the Australian Student Prize^[11] and was accepted into the University of Queensland to study medicine.^[12]

Gabbett was joint first author on the paper that demonstrated biallelic mutations in the mismatch repair genes are associated with malfomations of the brain.^[13][14][15] Gabbett and colleagues help define the oculoauriculofrontonasal syndrome.^[16][17] In 2015, Gabbett and his molecular genetic colleagues demonstrated the cause of Temple Baraitser syndrome, a condition that Gabbett clinically defined seven years earlier.^[8][9] Gabbett and Nick Fisk were able to postulate, with supportive molecular evidence, how semi-identical (sesquizygotic) twinning is the result of a single egg being fertilized by two sperm from the same man.^[6]

Gabbett has contributed to authorship of the Australasian clinical genetics training curriculum,^[18] and led the 2022 working party that made recommendations to medical schools on their genomics curriculum.^[19] For three years (2015-2018), he was chair of the scientific programme and the local organising committees (Lead Fellow) for RACP Congress, the annual scientific meeting of the Royal Australasian College of Physicians.^[20][21][22] Gabbett has served as president of the Australasian Association of Clinical Geneticists (2017-2019).^[23] From 2018 to 2022, Gabbett sat on Council of the Human Genetics Society of Australasia as Treasurer.^[24]