CASE-REPORT Low-level trisomy 14 mosaicism in a male newborn with ectrodactyly

Abstract

Complete trisomy 14 mosaicism is a rare chromosome disorder and was first reported in 1970. We describe a case of a male neonate who presented complete trisomy 14 mosaicism in only 4% of the cells from peripheral blood. A nineteen-day-old male neonate was born as result of the second pregnancy. The infant was delivered by cesarean section due to gestational hypertension and chronic fetal distress. The length of the term pregnancy was 37 weeks, the birth weight was 3.105 g, the length was 48 cm, and the head circumference was 35.5 cm. The baby remained hospitalized for 19 days in the neonatal intensive care unit due to respiratory distress syndrome and congenital malformations. Physical examination revealed a toned and normal activity, followed by phenotypic changes such as a broader forehead, formation of a cleft palate, hypertelorism, low-set ears, bilateral cryptorchidism, absence of the second toe of the left foot (ectrodactyly), and fusion of third and fourth toes in the right foot (bilateral syndactyly). Cytogenetic analysis was performed on peripheral blood cultures after hospitalization in the neonatal intensive care unit. Analysis of 200 G-banded metaphases showed that 192 (96%) had normal karyotype 46,XY and only 8 (4%) presented trisomy 47,XY,+14. It was not possible to perform cytogenetic analysis on the patient's parents. Our patient represents the first case of trisomy 14 disorder to present ectrodactyly.

Two Abnormal Cell Lines of Trisomy 14 and t(X;14) with Skewed X-Inactivation

“…Interestingly, our patient showed both severe intrauterine and postnatal growth retardation. Mosaic pigmentation is sometimes not described in neonates but reported later with advancing age [Shinawi et al, 2008;Rodrigues et al, 2016].…”

“…Usually mosaic trisomy 14 presents as free trisomy 14 [He et al 2014, Rodrigues et al, 2016Zhang et al, 2016;Yakoreva et al, 2018], Robertsonian translocation [Ozawa et al, 1984], and non-Robertsonian translocation 131 [Tunca et al, 2000]. Both free trisomy and Robertsonian translocations have the same genomic dosage.…”

Prevalencia de mosaicismos cromosómicos en 2.500 estudios citogenéticos realizados en un laboratorio de genética en el Estado de Rio de Janeiro, Brasil

“…Dentre os 19 casos abordados neste estudo, dois deles foram publicados em revistas científicas. Um deles é um caso raro de trissomia do cromossomo 14 em mosaico (47,XY,+14[8]/46,XY[192]) (RODRIGUES et al, 2016), apresentando mosaicismo em apenas 4% das células, sendo a menor porcentagem já encontrada para esta síndrome juntamente com o estudo de Fujimoto et al (1992). Interessantemente, não foi encontrada uma correlação direta entre a gravidade do fenótipo e a proporção de células com a trissomia do cromossomo 14.…”

Low-Level Trisomy 14 Mosaicism: A Carrier of an Isochromosome 14 and a Supernumerary Marker Chromosome 14

“…The most common clinical features are growth and psychomotor deficiency, developmental delay, and dysmorphic features. Dysmorphic features include dysplastic and/or malpositioned ears, cleft or high-arched palate, large mouth, hypertelorism, broad nasal bridge, and short neck [Shinawi et al, 2008;Salas-Labadía et al, 2014;Rodrigues et al, 2016]. Moreover, congenital heart disease, genitourinary abnormalities, body asymmetry, and abnormal skin pigmentation have also been reported [Shinawi et al, 2008].…”