Initially, Sovani et al (23) identified clonal chromosomal abnormalities including loss of a chromosome 6; extra material of unknown origin attached to the long arm of chromosome 12; and an unbalanced translocation
involving the short arm of a chromosome 6 and the long arm of a chromosome 14 in a case of OFMT.
The DS cases with unbalanced translocation
usually are de novo and nearly 25% result from familial transmission.
The male patient was diagnosed with a balanced three-way reciprocal translocation after his female partner suffered repeated miscarriages and an elective abortion due to the fact that the embryo was affected with an unbalanced translocation
Should a structural rearrangement occur in repetitive sequences, this step would remove the actual event; however, we chose to implement this step here to emphasize that the putative fetal de novo unbalanced translocation
for plasma C occurred in a background of unique sequences.
One with an unbalanced translocation
(11 and 13) of maternal origin, a strictly genetic anomaly.
Three children with an unbalanced translocation
resulting in partial Trisomy 8 and partial Monosomy 12 survived in this family, and all had dysmorphic features and severe intellectual handicap.
A woman pregnant with a male fetus affected by an unbalanced translocation
(46,XY, der(14;21)(q10;q10), + 21) was recruited with informed consent.
Chromosomal abnormalities, including trisomy 21 and an unbalanced translocation
, were detected by aCGH in two infants.
A karyotypic abnormality in SPENP has been described in a 43-year-old black woman; the abnormality consisted of an unbalanced translocation
between chromosomes 13 and 17: der(17)t(13:17)(q14:p11).
5) Abnormal segregation during meiosis can result in sperm with unbalanced translocations
Recent data from a study from the National Institute of Child Health and Human Development (NICHD) reveal that the prenatal detection rates for aneuploidy and unbalanced translocations
are comparable between microarray analysis and karyotyping.
PGD for detection of aneuploidies and unbalanced translocations
utilizes fluorescent in situ hybridization (FISH), in which a DNA probe that is coupled with a colored fluorescent marker is hybridized to the DNA in the test sample.