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07:42
Chromosome Preparation From Cultured Cells
Published on: January 28, 2014
[Familial chromosome X structural aberrations - case report]
Agnieszka Stembalska1, Ewa Barg, Anna Jakiel
1Katedra Genetyki Akademii Medycznej, Wroclaw. agnes@gen.am.wroc.pl
Pediatric Endocrinology, Diabetes, and Metabolism
|March 31, 2011
Summary
Chromosome X aberrations in women may not always cause abnormalities or affect fertility. These genetic variations are often discovered incidentally during medical evaluations.
Area of Science:
- Human Genetics
- Cytogenetics
- Reproductive Biology
Background:
- The X chromosome is crucial for ovarian function and growth, carrying approximately 1000 genes.
- X chromosome aberrations encompass a wide range of phenotypes influenced by aberration size, gene content, chromosome number, and inactivation patterns.
Observation:
- Two families with distinct X chromosome aberrations (dupXq/delXp and Xp deletion) were identified using GTG-banding and FISH.
- In both families, healthy, fertile women with X chromosome aberrations were identified, with no history of recurrent miscarriages or developmental delays.
Findings:
- Family A: A mother with mosaic Turner syndrome (mos 45,X/46,X,der(X)) gave birth to a daughter with a de novo structural X aberration of maternal origin.
- Family B: A mother with an Xp deletion (del(X)(p22.1p22.2)) had a daughter with Down syndrome and an additional X chromosome aberration.
Implications:
- X chromosome aberrations in women can be compatible with normal fertility and phenotype.
- Incidental diagnosis of X chromosome aberrations highlights the complexity of genotype-phenotype correlations in chromosomal abnormalities.
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