A rare case of mosaic partial tetrasomy 18p presenting with oligomenorrhea and intellectual disability: a case report

The patient's oligomenorrhea, distinctive features, and intellectual disability may be associated with a partial duplication of the short arm of chromosome 18. Previous reports on patients with tetrasomy 18p have focused primarily on preschool or prepubescent patients. Here, we present the first reported case of a 17-year-old female with mosaic tetrasomy 18p. The absence of fingerprints on the palms and oligomenorrhea may represent novel characteristics of this condition. For such rare chromosomal abnormalities, the combined use of G-banding, C-banding karyotype analysis, CNV-seq technology, and comprehensive clinical evaluation can facilitate early diagnosis, genetic counseling, and personalized treatment.