A rare case of extensive multiple idiopathic cervical root resorption with potential genetic predisposition was presented. A heathy 19-year-old Chinese male with no contributory medical or family/social history complained of pain during mastication that lasted for several months. Oral examination identified 7 missing teeth and external cervical root resorption involving 9 teeth. Comparison of orthopantomograms taken in May 2021 and February 2022 identified that cervical root resorption occurred in 22 teeth. Resorption commenced at the cementoenamel junction and progressed rapidly over the 9-month period. Laboratory test results were within normal limits. Trio-based whole-exome sequencing showed a missense mutation c.5630 C T in the filamin A (FLNA) gene at chromosome X of the subject. This is suggestive of the possibility of sex-linked recessive inheritance. This is the first study to report FLNA mutation in human subjects with cervical root resorption involving multiple teeth.