The clinical name for Down syndrome is trisomy 21, a condition in which a person is born with an extra chromosome, causing mild to moderate cognitive disability, developmental delays and physical challenges.

The Texas Rangers player, 28, will wear number 21 for the 2025 season in honor of his daughter Penelope, who was born with Down syndrome, according to the Major Baseball League. The genetic condition, known as Trisomy 21, results in an extra copy of chromosome 21.

Down Syndrome is also known as Trisomy 21, and Burger wants to raise awareness and contribute to research on the genetic condition.

Jake Burger is one of the Texas Rangers’ offseason additions. He explained how his daughter influenced his switch from number from 36 to 21.

ARLINGTON, Texas - New Texas Rangers corner infielder Jake Burger picked his new jersey number to honor his daughter. Burger will wear the number 21 with the Rangers this season. Burger chose the number in honor of his daughter, Penelope, who was born with Down syndrome.

Burger, who was acquired by the Rangers this offseason in a trade from the Miami Marlins, will honor his daughter.

Jake Burger will wear No. 21 after being acquired by the Texas Rangers. The number has special significance for his family after his daughter was born in October with Down syndrome.

The new Rangers first baseman announced Friday that he will wear No. 21 to pay tribute to Penelope, who was born with Down Syndrome, and to raise awareness for the genetic condition.