Prenatal diagnosis of paternal duplication of 11p15.5→14.3: Its implication of Beckwith-Wiedemann syndrome.

OBJECTIVE

To characterize a prenatally detected chromosomal aberration with molecular cytogenetic approaches and explore its relationship with Beckwith-Wiedemann syndrome (BWS).

CASE REPORT: A 33-year-old woman, gravida 2, para 0, was referred to our prenatal clinic at 20+ weeks due to an abnormal amniocentesis karyotyping finding, which showed 46,XY,add(11)(q24.2)dn. The mother conceived through in vitro fertilization-intracytoplasmic sperm injection (IVF-ICSI), then embryo transfer. Fetal ultrasound revealed a left-sided congenital diaphragmatic hernia, overgrowth of the fetus, and an enlarged placenta. After genetic counseling and careful deliberation by the family, the pregnancy was subsequently terminated at 22+ weeks of gestation, delivering a fetus weighing 810 g (85th to 90th centile) and a placenta of 325 g (85th to 90th centile). To further delineate the nature of the rearrangement involved in the defective chromosome 11, repeat chromosomal analyses, including array comparative genomic hybridization (aCGH) test and quantitative fluorescence-polymerase chain reaction (QF-PCR) using short tandem repeat (STR) markers, were performed by sampling fetal tissue. The final result confirmed a diagnosis of 46,XY,del(11)(q24.3q25),dup(11)(p14.3p15.5). The abnormal chromosome 11 was inherited from the father and the duplicated segment involved 11p15.5, a critical imprinting region for BWS.

CONCLUSION

We presented a prenatally detected chromosomal aberration characterized by paternal duplication of chromosome 11p15.5, which strongly related to the phenotypic manifestation of BWS.