Genetic heterogeneity of non-specific mental retardation.
OBJECTIVE
To explore genetic patterns of non-specific mental retardation (NSMR).


METHODS
Using segregation analysis, Finney method and Falconer method, the authors studied 157 pedigrees with NSMR selected in a population survey in Shandong province.


RESULTS
Ux U multiplex families may accept the autosomal recessive inheritance, Ux U total families is the autosomal recessive inheritance while it may be the multifactorial inheritance with major-gene effect, the frequency of sporadic cases is approximately 46%; Ux A mating families may keep the incomplete penetrance in autosomal dominant inheritance.


CONCLUSIONS
The genetic pattern of NSMR has the genetic heterogeneity.
Chen
J
J
Department of Medical Genetics, Shandong Medical University, Jinan, Shandong, 250012 P. R. China. chenjie81@163.net
Guo
Y
Y
Zhao
M
M
D005260:Female; D014644:Genetic Variation; D006801:Humans; D008607:Intellectual Disability / Q000235:genetics*; D008297:Male