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Human DNA Polymerase Gamma Mutation Database


All inquiries, additions to the list, and comments should be made to Bill Copeland.

To search for multiple exons, hold <Ctrl> while selecting multiple options.

Amino Acid Substitution: R227W
cDNA Position: 679 c→t (exon 3)
Disease Genetics Frequency Reference
PEO 36% of patients with sporadic PEO with multiple mtDNA deletions carry mutations in one of the three genes associated with familial arPEO or adPEO. Twinkle gene in 7% and POLG1 gene in 25% of our Italian and British patients with sporadic PEO. Found as c 7 out of 27patients w/sporadic PEO compared to 250 controls individuals. (Agostino et al., 2003)
PEO Found as compound in trans w/ S1176L.  Also, found as compound in trans with T251I-P587L. (Lamantea and Zeviani, 2004)
Alpers, Severe childhood multi-system disorder In Alpers found as compound with A467T. In severe childhood multi-system disorder found as compound with D1184N de Vries et al. , 2007 identified 1 (4.76%) children out of 21 with a POLG mutation that were known to have a mitochondrial disorder (de Vries et al., 2007)
Myopathy and gastrointestinal obstruction Found in trans w/ G848S with mtDNA depletion and Cox deficient muscle fibers (Giordano et al., 2009)
MDS Found in a large cohort study. (Hikmat et al., 2020)
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