The Messiah, His Brothers, and the Nations

Why does Matthew append and his brothers' to Judah and Jechoniah (1:2, 11)? Secondly, why does Matthew include the following four annotations: and Zerah by Tamar', by Rahab', by Ruth', and by the [wife] of Uriah' (1:3-6)? Jason B. Hood uses a composition critical approach in which he examines biblical genealogies and summaries of Israel's story' in order to shed light on these features of Matthew's gospel.