A Rare Triploidy Case with Long Term Survival: A Case Report Study

Abstract

Triploidy is the most frequent chromosome abnormality in the gestational age. According to the study, survival of more than 2 months in triploid patients is very rare. A 7-year-old girl with mild mental retardation with dysmorphism was referred for genetic counseling and clinical evaluation to Sarem medical genetics department (Tehran, Iran, 2013). Clinical features of the child were mental retardation, prominent upper lip, microgenitalia, prominent forehead, foot fingers syndactyly, and short hypoplastic 5th finger. G banding technique, skin biopsy, and Fluorescence in situ hybridization (FISH) testing were performed. Brain Imaging was evaluated. The karyotype of patient showed triploid (69, XXX) chromosome complement in all the metaphase spreads. However, two cell lines were found in metaphase of cultured cutaneous biopsy. The majority of the cells the body were triploid (69, XXX) and 16% of cells were diploid (46, XX). Findings of the FISH testing using X and Y Satellite enumeration probes in all studied peripheral blood lymphocyte (PBL) cells, included 3 signals and none signal respectively indicating X and Y chromosomes. Also, cultured of cutaneous biopsy finding showed 66% of cells had three signals (triploid) and 34 percent of cells had two signals (diploid) and mosaicism was confirmed. Karyotypes of parents and the brain imaging were normal. This study presents a rare case of triploidy with long survival with normal karyotypes of PBL and mosaicism in skin biopsy and interphase FISH.

Extended survival of a premature infant with a postnatal diagnosis of complete triploidy

“…In addition, one case5 reports a female child known to be alive at 7 years of age. Although peripheral blood typing confirmed 69,XXX, further analysis of cutaneous tissue in this case revealed a mosaic pattern of 46,XX in 16% of cutaneous cells.…”

“…Triploidy usually results in spontaneous abortion. The estimated prevalence of triploidy at 16–20 weeks’ gestation is 1 in 5000,2 and among live births, this is reduced to 1 in 10 000 3–5. Liveborn infants usually die early in the neonatal period, within hours or a few days of birth 4…”

Somatic Sex: On the Origin of Neoplasms With Chromosome Counts in Uneven Ploidy Ranges

“…On the other hand, the development of digynic triploid embryonic tissues prove that, given the proper circumstances, two appropriately functioning centrosomes can even continuously distribute hexaploid intermediates into regular stable triploid daughter cells. Such triploid conceptuses can sometimes fully develop and occasionally even survive for several months after birth (Sherard et al, 1986;Joergensen et al, 2014;Toufaily et al, 2016;Akhlaghdoust et al, 2017). Since mitotic hyperdiploid ALL cells also contain only two centrosomes, the same mode of division enables likewise their continuous, stable and faithful propagation (Molina et al, 2020).…”