Abstract
Trisomy 13 was first described by Patau in 1960. It is a rare genetic disease caused by having an extra copy of chromosome 13. Mosaic trisomy 13 happens when a percentage of the cells are trisomic for chromosome 13, while the remaining cells are euploid. Patau syndrome has a limited survival rate, and most of the carriers die before completing the first year of life. Unlike Patau syndrome, mosaic trisomy 13 is known for longer survival. It is associated with central nervous system malformations, cardiac defects, and psychomotor delay. We report a six-year-old male patient, the third child of a first-degree consanguinity. Born at term via emergency cesarean section due to meconium-stained amniotic fluid and fetal distress. Apgar score nine at one minute and nine at five minutes. Initial examination showed typical dysmorphic features like deep-seated eyes, small palpebral fissure, low set of ears, high arched palate, short neck, and right-hand polydactyly. The diagnosis was made through chromosomal analysis, and it revealed mosaic trisomy 13.