Genus Shamov officially in Russia is calculated from the "Prince of Kazan Shamov Schabas (1525-1590 gg.), butler Ali Shah, in 1550 - 1552 years accompanied his lord from Kazan to Moscow, and obviously it took Russian citizenship" (PSRL, 29, pp. 62 - 68).
The basis of the names can be compared with the Turkic-Persian Sham - Sham "light" or with the name of the city of Damascus - Sham (Baskakov, 1979, p. 138 Schabas - brave, young man; sham - a lamp).
Here are the official mention of our ancestors in the annals: "Initially, Shah Ali and magistrates have sent to Moscow Khan's butler Prince Schabas Shamov and nobleman Ivan Shishkin with the report to Ivan IV, what they were building a city on the Sviyaga and that Prince Silver returned from Kazan campaign, beating enemies with small losses, and local people want to serve the king (PSRL. T. XIII. P. 164, 465; T. XX. P. 481; Vol. XXIX. P. 62, 161).