Thomas C J, Kotze T J, Nash J M
Arch Oral Biol. 1986;31(3):145-7. doi: 10.1016/0003-9969(86)90119-6.
The Carabelli trait in South African negroids, caucasoids, Coloured (Peninsula and Namaqualand) and Indians, classified according to Alvesalo, Nuutila and Portin (1975; Acta odont. scand. 33, 191-197) showed generally peak frequency of expression for dm2 falling into class 3 and for M1 into class 4, that dm2 displays more negative expression (class 2 and 3) and M1 more positive expression (class 4 and 5) and that overall expression in dm2 is higher than in M1. The Indian group was an exception with peak frequencies in class 2 for dm2 and class 1 (right) and class 2 (left) for M1. There was no sex dimorphism and there was a tendency for concordance of expression between sides but not within sides.
根据阿尔韦萨洛、努伊蒂拉和波尔廷（1975年；《斯堪的纳维亚牙科学报》33卷，第191 - 197页）的分类，南非黑人、白种人、有色人种（半岛和纳马夸兰地区）以及印度人的卡氏特征显示，乳牙第二磨牙（dm2）通常在3类表现出最高的表达频率，第一恒磨牙（M1）在4类表现出最高的表达频率，即dm2显示出更多的阴性表达（2类和3类），M1显示出更多的阳性表达（4类和5类），并且dm2的总体表达高于M1。印度人群体是个例外，dm2在2类出现最高频率，M1在1类（右侧）和2类（左侧）出现最高频率。不存在性别二态性，并且两侧之间存在表达一致性的趋势，但同一侧内部不存在这种趋势。
