Prenatal Diagnosis of a Fetus with Partial Duplication and Deletion of Chromosome 18 Due to Maternal Pericentric Inversion 18

The phenotype of structural chromosome 18 mutations is highly heterogenous, clinical manifestations may range from mild to severe, they have been widely studied in the literature, however, there are few cases where two or more present same individual, reports these alterations caused by a maternal pericentric inversion and diagnosed prenatally even rarer. Affected individuals generally characterized low birth weight, intellectual disability, heart defects, musculoskeletal abnormalities, craniofacial anomalies, among others. We describe case masculine fetus non-consanguineous marriage obtained at week 29 gestation. 27-year-old mother, G2C1, she started antenatal care 11 pregnancy Hospital Universitario del Valle, Cali, Colombia. Ultrasound 11th gestation showed 3.9 mm nuchal translucency (>95p), subsequently 18th new ultrasound found 6mm (>95p); suspecting chromosomal aberration an amniocentesis was carried out 18th, 756-band resolution karyotype reported: partial trisomy (from 18p.11.2 centromere 18q11.22 18qter), monosomy 18pter 18p11.2 18q11.2). parents also underwent genetic testing, mother exhibited (46,XX,inv(18)(p11.2q11.2), no abnormalities were father’s material. At 24 detailed anatomy left diaphragmatic hernia, multicystic dysplastic kidney, polyhydramnios. After explaining diagnosis providing counseling, patient requested voluntary interruption as established c-355/06 law Colombian constitutional court. A 1,180 g obtained. rearrangement this be explained error meiosis, oogenesis. During meiosis 2 anomalous disjunction took place, short arms separated long arms, latter isochromosome one that received, thus, leading described mutation. aim report provide scientific literature first prenatal with specific bands 1, due inversion, while highlighting value early diagnosis, order make choices regarding pregnancy, follow up, planning delivery method, allowing adequate reproductive counseling for future pregnancies.