Prenatal diagnosis of tetrasomy 47,XY, + i(12p) confirmed by in situ hybridization

Abstract

A case of tetrasomy i(12p) detected prenatally is reported. The patient, a black, 32-year-old G3P2002 at 24 weeks' gestation with an unremarkable family history presented herself for prenatal care. Ultrasound examination showed a fetus with diminished femoral and humeral lengths, and hydramnios. A level II scan confirmed the presence of an omphalocele. Amniocentesis at 31 weeks showed 47,XY,+i(12p) karyotype. An infant with multiple congenital anomalies was delivered at 34 weeks. The infant died after 5 h. Genetic and ultrasonographic examinations in the third trimester were helpful in the investigation of this fetus with multiple congenital anomalies. The careful, complete team counselling afforded by this approach enabled the mother and family to be well adjusted to the strong possibility (and subsequent reality) of an abnormal infant.

The Use of Interphase Fish for Prenatal Diagnosis of Pallister–killian Syndrome

“…The marker chromosome was identified as an i(12p) using a cDNA probe for the KRAS2 gene, which maps to chromosome 12p12. A premature male infant with multiple congenital anomalies was born at 34 weeks, but died after 5 h (Shivashankar et al, 1988). A total of 20 cases have been diagnosed following amniocentesis for either AMA or detection of fetal anomalies (Gilgenkrantz et al, 1985;Lopes et al, 1985;Hunter et al, 1986;Steinbach and Rehder, 1987;Warburton et al, 1987, case 3;Shivashankar et al, 1988;Eydoux et al, 1989;Soukup and Neidich, 1990;Speleman et al, 1991, case 4;Blancato et al, 1991Blancato et al, , 1992McLean et al, 1992;Priest et al, 1992;Tejada et al, 1992;Bergoffen et al, 1993, case 3;Donnenfeld et al, 1993, cases 8 and 12;Larramendy et al, 1993;Wilson et al, 1994, cases 1 and 2; Los et al, 1995).…”

“…Prenatal diagnosis has been previously reported in 23 cases of PKS (Gilgenkrantz et al, 1985;Lopes et al, 1985;Hunter et al, 1986;Steinbach and Rehder, 1987;Shivashankar et al, 1988;Eydoux et al, 1989;Soukup and Neidich, 1990;Bresson et al, 1991;Sharland et al, 1991;Speleman et al, 1991;Blancato et al, 1992;Bernert et al, 1992;McLean et al, 1992;Priest et al, 1992;Tejada et al, 1992;Bergoffen et al, 1993;Donnenfeld et al, 1993;Larramendy et al, 1993;Wilson et al, 1994;Los et al, 1995). Both chorionic villi and amniocytes appear to maintain the isochromosome; however, the level of mosaicism varies greatly between individuals.…”

Foetal Autopsy-Categories and Causes of Death

“…The trisomy D [12][13][14][15] chromosomal anomaly exhibits variable Placental maturation, reduced villous vasculature and giant cytophoblast in 50% or more of villi [Table/ Fig-4]. Tetrasomy 12 is a well-recognised chromosomal error with usually lethal anomalies, severely malformed fetus with normal birth weight and essentially normal placenta [13]. Shepard et al, [14] undertook 20 y analysis of aborted specimen and found that 19% of fetus had a localized defect.…”

Prenatal diagnosis of the Pallister‐Killian mosaic aneuploidy syndrome by CVS

“…This syndrome is identical to that described by Killian and Teschler-Nicola [19811. Subsequent examinations of patients with Teschler-Nicola Killian syndrome demonstrated the presence of aneuploid cell lines with an isochromosome 12p or additional chromosomal material derived from 12p [Buyse and Korf, 19831. Gene dosage studies of the LDH isoenzymes [Steinbach and Rehder, 1987;Warburton et al, 1987;Reynolds et al, 19871 and molecular hybridization with KRAS 2 probes [Peltomaki et al, 1987;Shivashankar et al, 1988;Zangh et al, 19891 provided additional evidence on the origin of the extra chromosome.…”