The prenatal diagnosis of familial satellited Yq chromosomes
To report a rare chromosomal abnormality, familial satellited Y chromosome (Yqs), in 3 Turkish prenatal cases. Material and methods: Metaphase chromosomes were prepared from amniocytes for prenatal cases and from lymphocytes for their fathers according to the standard methods. Results: In all cases, the analysis of all GTG-banded metaphases showed satellites on the long arms of chromosome Y as 46, XYqs karyotype. The indications for cytogenetic study were advanced maternal age and abnormal ultrasonographic findings with increased risk in the first trimester screening test. Cytogenetic studies of the fathers revealed that the Yqs were inherited. The satellites were positively stained by the silver-NOR technique, suggesting that the NORs were active for all cases. In accordance with the literature and the finding of paternal inheritance in all cases, genetic counselling was given to the families. The families decided to continue the pregnancies and all 3 babies were born at term without any dysmorphic features. Conclusion: Proper genetic counseling requires the accumulation of detailed information about the clinical follow-up evaluations and determination of whether the satellited Yqs is de novo or familial.
The prenatal diagnosis of familial satellited Yq chromosomes
To report a rare chromosomal abnormality, familial satellited Y chromosome (Yqs), in 3 Turkish prenatal cases. Material and methods: Metaphase chromosomes were prepared from amniocytes for prenatal cases and from lymphocytes for their fathers according to the standard methods. Results: In all cases, the analysis of all GTG-banded metaphases showed satellites on the long arms of chromosome Y as 46, XYqs karyotype. The indications for cytogenetic study were advanced maternal age and abnormal ultrasonographic findings with increased risk in the first trimester screening test. Cytogenetic studies of the fathers revealed that the Yqs were inherited. The satellites were positively stained by the silver-NOR technique, suggesting that the NORs were active for all cases. In accordance with the literature and the finding of paternal inheritance in all cases, genetic counselling was given to the families. The families decided to continue the pregnancies and all 3 babies were born at term without any dysmorphic features. Conclusion: Proper genetic counseling requires the accumulation of detailed information about the clinical follow-up evaluations and determination of whether the satellited Yqs is de novo or familial.
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