Prenatal presentation of 49,XXXXY syndrome

Clinical experience with sex chromosome aneuploidies detected by noninvasive prenatal testing (NIPT): Accuracy and patient decision‐making

“…While SCAs as a group are as common as autosomal aneuploidies in low‐risk populations, NIPT performance is not as good for SCAs as compared to trisomies 21, 18, and 13 because of fetal mosaicism, confined placental mosaicism, underlying maternal X chromosome variation, and/or fetal aneuploidy diagnoses outside the scope of NIPT validation . The majority of the published data regarding positive and negative predictive values comes from commercial labs in addition to a few retrospective studies from clinical practices .…”

49,XXXXYsyndrome: A study of neurological function in this uncommon X and Y chromosomal disorder

“…Case studies have noted epicanthic folds, upslanting palpebral fissures, broad nasal bridge and nose, low‐set ears, arched eyebrows, synophrys, mild hypoplasia of the corpus callosum on brain neuroimaging studies and hypertelorism. (Argun et al, 2015; Burgemeister et al, 2019; Etemadi, Basir, & Ghahremani, 2015; Özcan & Şahin, 2017; Schluth et al, 2002; Sprouse et al, 2013; Stover, Cowan, Cross, Hoffman, & Craigo, 2017). Less common features include cleft lip and palate and cardiac disorders (Gropman et al, 2010).…”

Close but not quite: Two cases of sex chromosome aneuploidies outside the scope of cell free DNA screening

“…Most, if not all, commercial laboratories offering cfDNA screening are also validated to report sex chromosome aneuploidy. Yet, accurate detection of sex chromosome aneuploidies by cfDNA screening has shown to be challenging due to fetal mosaicism, confined placental mosaicism, underlying maternal diagnoses, and/or fetal aneuploidy diagnoses outside the scope of cfDNA validation …”