Karyotype and phenotype association in Turner syndrome with non-mosaic X chromosome structural rearrangements: Systematic review

Abstract

Turner syndrome is a chromosomal disorder, characterized by the partial or total deletion of one X chromosome, resulting in various karyotypes that presumably lead to different phenotypes. However, most studies find it difficult to predict phenotypes from karyotypes due to the presence of mosaicism. The purpose of this study is to clarify the relationship between karyotype and phenotype in Turner syndrome with non-mosaic X chromosome structural rearrangements. A systematic literature search was conducted using Medline and Embase classics plus Embase between 1947 and September 2023. A total of 487 Turner women with non-mosaic X chromosome structural rearrangements were included from the 69 studies. The prevalence of short stature was 72.4% in Turner syndrome with non-mosaic X chromosome structural rearrangements, 80.1% in the short arm deletion group (del (Xp)), 75% in the del(X)(p22.3) group, 65.8% in the del(X)(p21) and del(X)(p22) group, and 37.5% (20%–66.7%) in the long arm deletion group (del(Xq)). The prevalence of ovarian dysfunction was 78.8% in Turner syndrome with non-mosaic X chromosome structural rearrangements, 72.5% in the del (Xp) group, 27.6% in the del (X)(p22.3) group, 33.3% in the del (X)(p21) and del(X)(p22) group, and 94.6% in the del (Xq) group. The recognition of X chromosome breakpoints is useful in the management of Turner syndrome complications, since some phenotypes are unique depending on the deletion region. Ovarian dysfunction is significantly related to karyotype, so the identification of karyotypes in Turner syndrome is important for managing ovarian dysfunction and predicting future fertility.