Clinical and genetic analysis in two families with huntington disease / 安徽医科大学学报

ABSTRACT

Objective To investigate the relation between CAG expansion length and clinical symptoms in hunting-ton′s disease ( HD) ,and to evaluate the value of CAG age product ( CAP score) in the clinical practice. Methods Two Han Chinese HD family members’ clinical data, including clinical symptoms and signs, the Cambridge cog-nitive examination-Chinese version ( CAMCOG-C) and Hamilton depression rating scale were collected, and these two families pedigree trees were drawn. Volunteers peripheral venous blood was extracted to pursue IT15 genetic test. CAP scores among members whose CAG repeat number was more than 35 were calculated. Results The pedi-gree trees indicated that HD was autosomal dominant inheritance. Among 6 participants who had pursued genetic test,1 was normal and 5 were carring expanded allele; according to fomal clinical diagnosis criteria,2 participants were in manifest period and 3 were in pre-manifest period. Individuals in manifest period had clinical triad,and in-divudals in premanifest period,though hadn’ t been clinically diagnoseded, were characterized by subtle motor,cog-nitive,behavioural or personality changes. Conclusion HD prior to clinical diagnosis may have mild clinical symptoms;the more CAG repeats indicate earlier onset, the heavier the symptoms. CAP score as a parameter, combined with the CAG repeat number and the age, is of great significance for predicting the onset age, clinical tri-al subjects grouping, and give a better understanding of the natural history of HD.