It is impossible to know if the 144,000 are actual Israelites from the 12 tribes simply due to the fact that the 10 northern tribes apostatized from God and were carried away to Assyria in 722 BC. “In the ninth year of Hoshea, the king of Assyria took Samaria and carried Israel away to Assyria, and placed them in Halah and by the Habor, the River of Gozan, and in the cities of the Medes” (2 Kings 17:6). The 10 exiled tribes intermarried with the Assyrians, and lost their distinct identity.
Later on the tribes of Judah and Benjamin were also taken captive to Babylon. But after spending 70 years, thousands of them returned to Israel. However, history doesn’t record any big exodus for the ten tribes from Assyria back to Israel.
The King of Assyria relocated a group of people from pagan nations back to Samaria: “And the king of Assyria brought men from Babylon, and from Cuthah, and from Ava, and from Hamath, and from Sepharvaim, and placed them in the cities of Samaria instead of the children of Israel: and they possessed Samaria, and dwelt in the cities thereof” (2 Kings 17:24).
And the King of Assyria sent one Hebrew priest back from Assyria to teach these relocated pagans about the God of Israel (2 Kings 17:27). These pagans became known as the Samaritans. The Jews hated the Samaritans because they were not real Israelites neither in blood nor in faith.
Genealogists today cannot determine the pure descendants of the 10 tribes because these tribes were so thoroughly dispersed around the world and absorbed as the Lord predicted for their apostasy: “And they shall know that I am the LORD, when I shall scatter them among the nations, and disperse them in the countries” (Ezekiel 12:15).
The New Testament viewed believers not in a literal way but as spiritual Israelites regardless of whether they were Jews or Gentiles by blood: “For he is not a Jew who is one outwardly, nor is circumcision that which is outward in the flesh; but he is a Jew who is one inwardly; and circumcision is that of the heart, in the Spirit” (Romans 2:28,29 also Galatians 3:29).
In His service,