Human Tails and Whole Exome Sequencing Findings: Is There any Association? A Case Report

Abstract

Introduction: The human tail is a rare congenital condition characterized by a caudal cutaneous appendage, primarily located in the lumbosacral region. These tails are often associated with other congenital malformations, most notably spinal dysraphism. Case Presentation: A 3-week-old male neonate was referred to the Baqiyatallah Pediatric Clinic in Tehran, Iran, due to a 12-cm-long congenital tail-like appendage in his lumbosacral region, which contained only soft tissue upon palpation. There was no apparent neurological deficit on physical examination or magnetic resonance imaging. No other concomitant malformations were present. The parents were consanguineous, and a previous pregnancy had been terminated at 18 weeks of gestation due to a prenatal diagnosis of a neural tube defect. As a result, genetic consultation and whole exome sequencing were performed. Some phenotype-related variants of uncertain significance were detected, and the baby was also found to be heterozygous for oculocutaneous albinism. Conclusions: Although some genetic variants of uncertain significance and a pathogenic variant associated with albinism were identified in this case, the absence of other manifestations beyond the tail and the lack of literature on this topic make the clinical implications of genetic testing in human tails unclear. Further investigation is required to understand these implications.