EOMES (eomesodermin homolog), also known as TBR2 (T-box-brain2), is the 686 amino acid human homolog of the mouse Eomes protein that contains one T-box DNA binding domain. Genes that contain T-box domains encode proteins that function as transcription factors and are often involved in the regulation of various developmental events. Localized to the nucleus and expressed in the developing brain, EOMES is thought to be involved in neuronal migration and division and may play a role in trophoblast development and gastrulation. Silencing of the EOMES gene can cause mutated or arrested development and may lead to microcephaly disorders which are characterized by reduced head circumference and a malformed brain.