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Dechorionation of Medaka Embryos and Cell Transplantation for the Generation of Chimeras
Published on: December 22, 2010
Chimerism resulting from parthenogenetic activation and dispermic fertilization
Johanna Winberg1, Peter Gustavsson, Kristina Lagerstedt-Robinson
1Department of Molecular Medicine and Surgery and Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.
American Journal of Medical Genetics. Part A
|August 31, 2010
Summary
Human chimerism, where one individual develops from two zygotes, was investigated in a patient with a rare 46,XX/47,XY,+14 karyotype. Molecular analysis suggests this chimerism resulted from dispermic fertilization of a parthenogenetically activated egg.
Area of Science:
- Genetics
- Developmental Biology
- Reproductive Medicine
Background:
- Whole-body human chimerism, a rare condition arising from two zygotes forming one individual, presents diagnostic challenges.
- Understanding the molecular basis of chimerism is crucial for accurate diagnosis and clinical management.
Observation:
- A patient with ambiguous genitalia, cryptorchidism, pigment anomalies, and normal psychomotor development exhibited a 46,XX/47,XY,+14 karyotype.
- Cytogenetic and molecular analyses, including karyotyping, interphase-FISH, array-CGH, and polymorphic marker analysis, were performed on various tissues.
Findings:
- Analysis revealed the presence of 47,XY,+14 cells, with two paternal alleles and homozygous maternal alleles detected at 48 loci.
- Absence of four alleles indicated dispermic fertilization of a parthenogenetically activated oocyte as the mechanism for chimerism.
Implications:
- Cytogenetic findings initially suggestive of mosaicism may represent chimerism, necessitating advanced molecular investigation.
- The clinical outcomes for patients with mosaic or chimeric genetic aberrations remain difficult to predict, highlighting the need for further research.
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