Arwert F, Porck H J, Fràter-Schröder M, Brahe C, Geurts van Kessel A, Westerveld A, Meera Khan P, Zang K, Frants R R, Kortbeek H T
Hum Genet. 1986 Dec;74(4):378-81. doi: 10.1007/BF00280489.
Human transcobalamin II (TC2), a vitamin B12 binding serum protein, is synthesized and secreted into the medium by cells growing in vitro. Mouse-man somatic cell hybrids were analyzed in order to map the locus of TC2. The presence of human TC2 in the culture media was correlated with the results of genetic marker and chromosome analysis of the hybrid cells. Chromosome 22 showed 100% concordancy. However, chromosome 6 (90% concordancy) and chromosome 7 (96% concordancy) were not completely excluded. Meningioma cells obtained from patients heterozygous for TC2 showed a concomitant loss of one chromosome 22 and one of the TC2 alleles, strongly supporting the assignment to chromosome 22.
人转钴胺素II（TC2）是一种维生素B12结合血清蛋白，由体外生长的细胞合成并分泌到培养基中。为了定位TC2的基因座，对小鼠-人体细胞杂种进行了分析。培养基中人类TC2的存在与杂种细胞的遗传标记和染色体分析结果相关。22号染色体显示出100%的一致性。然而，6号染色体（一致性为90%）和7号染色体（一致性为96%）并未被完全排除。从TC2杂合的患者获得的脑膜瘤细胞显示出一条22号染色体和一个TC2等位基因的同时缺失，有力地支持了将其定位于22号染色体。
