J Genet Med.  2008 Jun;5(1):61-64.

Pseudoisodicentric X chromosome in a female with primary amenorrhea

• Park SH
• Shim SH
• Chin MU
• Kang SJ
• Bae SM
• Sohn SM
• Cha DH
• Yoon TK
• Cho JH

Abstract

A 24-year-old female with primary amenorrhea was referred for a chromosome study. The karyotype of the patient was 46,X,der(X) under initial GTG-banding analysis. Fluorescence in situ hybridization (FISH) analysis with an LSI Kallmann (KAL) region probe [probes for Xp22.3(KAL) and CEP(X) for control] was carried out. The abnormal chromosome was KAL- and CEP(X)x2. In addition, interphase FISH analysis revealed the patient to be mosaic for two different cell lines: 90% of cells had three signals and 10% of the cells had only one signal for CEP(X). Based on these results, the karyotype of the patient was 45,X/46,X,psu idic(X)(p22.1), which is partial trisomy for Xqter-->Xp22.1 and partial monosomy for Xpter-->Xp22.1. This karyotype was considered a variant of Turner syndrome. In summary, Idic(X) and low-level mosaicism was successfully characterized by FISH analysis with a CEP(X) probe.

Keyword

Pseudoisodicentric X chromosome; Variant Turner syndrome; Interphse FISH; low level mosaicism

MeSH Terms

Amenorrhea
Chromosome Deletion
Female
Fluorescence
Humans
In Situ Hybridization
Interphase
Karyotype
Mosaicism
Trisomy
Turner Syndrome
X Chromosome
Young Adult