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Study on isochromosomes: clinical experience from a tertiary referral center

ABSTRACT: Isochromosomes are structural chromosomal abnormalities associated with diverse clinical phenotypes. This retrospective study analyzed 99 cases of isochromosomes, including 69 postnatal and 30 prenatal cases, to investigate chromosomal distribution, parental inheritance, and risk factors. Karyotyping and cytogenetic analyses identified that isochromosomes predominantly involved the X chromosome (86.7%, 86/99). Among postnatal cases, 99.6% (68/69) exhibited sex chromosomal isochromosomes, with the most common karyotypes being 45,X/46,X,i(X)(q10) (40.5%) and 46,X,i(X)(q10) (39.1%). In prenatal cases, 63.3% (19/30) involved sex chromosomal isochromosomes, while 36.7% (11/30) involved autosomal isochromosomes. Parental chromosomal analysis for 69.0% (20/29) of fetuses showed normal results, suggesting that isochromosomes are predominantly de novo mutations. Advanced maternal age was significantly associated with autosomal isochromosomes (63.6% vs. 31.6% in sex chromosomal cases, p < 0.05). Ultrasound abnormalities were detected in 90.9% of autosomal cases, while non-invasive prenatal testing (NIPT) was the primary detection method for sex chromosomal isochromosomes (47.4%). These findings highlight the significant role of advanced maternal age in autosomal isochromosomes and underscore the importance of ultrasound for autosomal cases and NIPT for sex chromosomal isochromosomes in prenatal screening.

ORGANISM(S): Homo sapiens

PROVIDER: GSE291164 | GEO | 2026/03/07

REPOSITORIES: GEO

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Study on isochromosomes: clinical experience from a tertiary referral center

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