Isaiah 1.9
Septuagint

kai 
ei mh kurioV sabawq egkatelipen hmin sperma, wV Sodoma an egenhqhmen, kai wV  Gomorra an omoiwqhmen

New Testament - Romans 9.29

kai kaqwV proeihken HsaiaV: 
ei mh kurioV sabawq egkatelipen hmin sperma, wV Sodoma an egenhqhmen kai wV  Gomorra an wmoiwqhmen

Septuagint

And if the Lord of Sabaoth had not left us a seed, we should have been as Sodoma, and we should have been made like unto Gomorrha

New Testament

And, as Isaiah hath said before, Except the Lord of Sabaoth had left us a seed, We had become as Sodom, and had been made like unto Gomorrah

Masoretic Text

Except Jehovah of hosts had left unto us a very small remnant, we should have been as Sodom, and we should have been like unto Gomorrah

Comments:  NIV:  “Unless the LORD Almighty had left us some survivors, we would have become like Sodom, we would have been like Gomorrah.”  The MT does not speak of a “seed.”