Background: Human respiratory syncytial virus (RSV) is a primary etiological agent responsible for lower respiratory tract infections in children and older adults. The ON1 genotype replaced all previous strains of RSV-A and is characterized by a 72 base pair duplication in the G gene. Recent studies have reported the absence of this distinct feature. We examine publicly available RSV-A sequences to investigate the loss of this duplication. Methods: RSV-A G-gene and whole genome sequences from human samples collected between January 2010 and December 2023 were downloaded from the (GISAID) EpiRSV database. A total of 15,757 sequences classified as ON1 (alias A.D) were investigated. Sequence metadata including sample collection date, country of submission, and sequencing methods were recorded for RSV ON1 sequences missing the 72 base pair duplication. MAFFT and IQTREE2 were used to generate a maximum likelihood phylogenetic tree. Results: 417 sequences from 27 countries with sampling between 2010 to 2023 were identified without the characteristic 72 base pair duplication. All RSV-A sequences available from Cambodia and Pakistan from 2010-2023 lack the duplication while the remaining 25 countries report RSV-A sequences with and without the duplication. A phylogenetic tree was constructed, revealing that all global sequences with and without the duplication cluster together. Amino acid sequences of ON1 with and without the duplication were examined, showing shared mutations surrounding the duplication site. Conclusions: RSV-A ON1 sequences without the duplication are rare. The absence of the duplication does not interfere with phylogenetic relatedness among sequences with the duplication. The biological and clinical relevance of RSV-A ON1 viruses lacking the G gene duplication require further research.