Это работа лингвистов, которые реконструируют протомонгольский вариант.
Там есть и протоалтайский вариант:
Proto-Altaic: *šā̀k`a
Nostratic: Nostratic
Meaning: white
Russian meaning: белый
Turkic: *čakɨr
Proto-Turkic: *čakɨr
Altaic etymology: Altaic etymology
Meaning: light grey, greyish blue
Russian meaning: светло-серый, серовато-голубой
Karakhanid: čaqɨr (MK, Tefs.) (of eyes)
Turkish: čakɨr
Tatar: čaɣɨr (of eyes)
Middle Turkic: čaqɨr (Sangl.)
Uzbek: čaɣir-qanɔt 'a white-eyed dunbird, нырок белоглазый'
Uighur: čeqir (of eyes)
Turkmen: čaqɨr 'dried in the sun, bleached'
Halaj: čaqɨr 'yellow'
Kirghiz: čekir 'grey (of eyes), wall-eye'
Kazakh: šaɣɨr 'grey (of eyes, horses)', šegir 'grey (of eyes)'
Noghai: šaɣɨr 'colourless (of eyes)'
Bashkir: šaɣɨr 'whitish'
Balkar: čaɣɨr 'variegated'
Gagauz: čaqɨr
Karakalpak: šegir (of eyes)
Comments: VEWT 96, TMN 2, 77, EDT 409, Федотов 2 387. Despite Fedotov čokur 'variegated' is not related, it is < Mong. čobkur (v. sub *šop`é). Despite Räsänen borrowed from Mong. can be only Yak. čakɨr 'white (of a horse)' (cf. also Dolg. čakɨr, see Stachowski 72), and perhaps the front-row forms (Kirgh. čekir, Kaz. šegir, KKalp. šegir - because of their restriction to the Kypch. area); but Mong.. čakir / čekir 'whitish' is itself an obvious Turkism (see TMN ibid., Clark 1977, 134 with doubts). The root should be distinguished from nasalized forms: Oyr. čaŋqɨr, Chuv. senker, Yak. čeŋgir, ǯeŋgir, Kirgh. čenkil, čaŋɨl with the same set of meanings ('whitish, blue', often of eyes) = Mong. (Khalkha) cenxer id.; those should be compared with Tokh. A, B tseṃ 'blue (of eyes)', Pers. zangār 'verdigris', whence Tat. zäŋgär (from Pers. zang 'rust', further derived with *zā'to leave, remain', Sak. ysāyä 'rust', Osset. zgä, see Bailey 348-349). This is most probably an Iranian loanword in Turkic, Tokh. and Mong. (although a Chinese origin - cf. MC 青 chieŋ 'blue' - is also possible). Cf. VEWT 104 (Turk. < Mong.), 531.
Mongolian: *čagaɣan
Proto-Mongolian: *čagaɣan
Altaic etymology: Altaic etymology
Meaning: 1 white 2 to become white
Russian meaning: 1 белый 2 белеть
Written Mongolian: čaɣan 1 (L 158), čaji- 2 (L 160)
Middle Mongolian: čaxan (HY 41), čaqan, čaqa'an (SH) 1, čaiji- (SH) 2, čaɣan (IM) 1, čaɣan, čiɣan (MA) 1
Khalkha: cagān 1, caj- 2
Buriat: sagān 1, saj- 2
Kalmuck: caɣān 1, cǟ- 2
Ordos: čagān 1, čǟ- 2
Dongxian: čǝGan 1
Baoan: čixaŋ 1
Dagur: čigān (Тод. Даг. 181, MD 129) 1; čē- 2
Shary-Yoghur: čaɣān 1; čei- 2
Monguor: ćiGān (SM 447) 1, ćī- (SM 441), ćē- (SM 447), ćai- (Minghe) 2
Mogol: čaɣōn; ZM čaɣɔ̄ (13-7), KT čaɣɔ̄n (18-4a)
Comments: KW 419, 425, MGCD 557, 560, TMN 1, 177. Cf. *čege-ɣen 'light, white' (KW 426). Mong. > Man. čagan 'white, white paper, books' (see Rozycki 42).
Tungus-Manchu: *šāk-
Comments: Владимирцов 248, Цинциус 1984, 12-13, АПиПЯЯ 293. A Western isogloss. The Mong. variants *čaji- / *čeji- reflect most probably a merger with the root *šā̀ŋu 'clear, light' q. v.