The Turner syndrome life course project: Karyotype‐phenotype analyses across the lifespan

Abstract

Karyotype may play an important factor against stratifying risk of comorbidity in TS and should be taken into consideration when managing adults with TS. Further investigations of the isochromosome (Xq) and ring groups are necessary to further clarify their associations with comorbidities.

Pregnancies and obstetrical prognosis after oocyte donation in Turner Syndrome: A multicentric study

“…It is due to the absence or structural abnormality of one of the X chromosome, with various degrees of mosaicism. Mosaicism attenuates the phenotype of Turner syndrome, especially the anthropometric data and the cardio-vascular morbidities [5,6]. Diagnosis of mosaic forms is established 8 years after the monosomic ones [7].…”

Liver biochemical abnormalities in Turner syndrome: A comprehensive characterization of an adult population

“…4,5 Previous studies investigating elevated LFTs and autoimmunity have yielded controversial results. 4,5,13,14 Recently, an association between higher alanine aminotransferase (ALT) levels and ring X karyotype was found in a large TS population, 15 whereas prior studies had shown no association with TS-karyotypes. Finally, cohort studies have suggested that the architectural liver changes described in TS may be the consequence of a primary vascular derangement.…”

Mosaic Turner syndrome shows reduced phenotypic penetrance in an adult population study compared to clinically ascertained cases

“…Indeed two additional previously known Turner syndrome cases were not detected by the SNP array method because they had loss of Xp and gain of Xq making the overall X chromosome dosage not significantly different from normal 46,XX. We suspect that these are isochromosomes, which contribute to about 15% of Turner syndrome cases in other published series 18,26 . We adapted our protocol to find additional cases with non-aneuploid X chromosome abnormalities and found a total of 5 cases of suspected 46X, i(Xq) and 9 with X chromosome deletions, although we were not able to validate these findings with an independent technology.…”

“…The majority of these women were mosaic. The published prevalence of Turner syndrome is 1/2,500, however only approximately 60% of those Turner syndrome cases are caused by 45,X or 45,X/46,XX mosaicism, the rest being due to other abnormalities such as deletions or isoXq 13,18 , thus the prevalence of aneuploidy causing Turner syndrome is around 1/4,200.…”