Background: Phenotypic variability of Turner syndrome (TS) challenges clinicians, and undiagnosed mosaicism may lead to conflicting results of karyotype-phenotype correlations. This study assessed the extent of phenotypic variability and investigated the presence of karyotype-phenotype correlations.
Methods: The sample comprised 80 patients with ≥50 cells analyzed in karyotype. Twenty were 45,X/46,X,+mar; three groups of 20 patients were constructed by matching those girls with the nearest-aged patient with 45,X, 45,X/46,XX and 45,X/46,X,i(Xq) or 46,X,i(Xq) karyotype.
Results: Data were obtained on height z-score, dysmorphic features, echocardiogram and urinary system sonography. The number of dysmorphic features ranged from one to 16 and was not correlated to age at diagnosis or height. The groups did not differ in height, number of dysmorphic features, cardiovascular and urinary system anomalies and frequency of any specific feature, except for short fourth metacarpal.
Conclusions: Wide phenotypical variability of TS may be objectively described and its clinical picture is not correlated to karyotype.
The authors are grateful to the Cytogenetics Laboratory of the Department of Medical Genetics of the University of Campinas (UNICAMP).
Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
Research funding: This work was supported by Brazil’s National Council for Scientific and Technological Development (CNPq/PIBIC).
Employment or leadership: None declared.
Honorarium: None declared.
Competing interests: The funding organization(s) played no role in the study design; in the collection, analysis, and interpretation of data; in the writing of the report; or in the decision to submit the report for publication.
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