Table 1.

Studies performed on measuring the possible heritability of gastroesophageal reflux disease and the severity of reflux symptoms among twins and family members and on identifying the risk genetic loci for gastroesophageal reflux disease

Studies
Twin and family studies
Cameron A et al[37]	↑ Heritability of GERD, ↑ symptoms in MZ
Mohammed I et al[38]	↑ Heritability of GERD, ↑ symptoms in MZ
Reding-Bernal A et al[39]	↑GERD symptoms severity in families in Mexico
GERD risk genetic loci studies
Ghoshal and Chourasia[8]	> 10 genes, up/down regulating GERD
Liu WF et al[40]	C allele in FOX1 rs9936833, A allele in MHC rs9257809 : ↑reflux symptoms
Gharahkhani P et al[41]	rs10419226 (chr 19), rs2687201 (chr 3) : ↑GERD symptoms
Bonfiglio F et al[35]	> 30 susceptible gene loci for GERD

GERD: Gastroesophageal reflux disease; MZ: Monozygotic twins; chr: Chromosome.