De Jonghe P, Timmerman V, FitzPatrick D, Spoelders P, Martin J J, Van Broeckhoven C
Flanders Interuniversity Institute for Biotechnology (VIB), Born Bunge Foundation (BBS), University of Antwerp (UIA), Antwerpen, Belgium.
J Neurol Neurosurg Psychiatry. 1997 Jun;62(6):570-3. doi: 10.1136/jnnp.62.6.570.
Charcot-Marie-Tooth disease type 2 (CMT2) or hereditary motor and sensory neuropathy type II (HMSN II) is an inherited axonal neuropathy of the peripheral nervous system. Three autosomal dominant CMT2 loci have been located on chromosomes 1p35-p36 (CMT2A), 3q13-q22 (CMT2B), and 7p14 (CMT2D) indicating that CMT2 is a genetically heterogeneous disorder.
A CMT2 family was examined for linkage to the CMT2A, CMT2B, and CMT2D loci using short tandem repeat polymorphisms.
Suggestive evidence for linkage to 3q13-q22 was found. Recombinations occurred with markers D3S1769 and D3S1267 indicating that the CMT2B locus is located distal to D3S1267 and resides in an interval of 25 cM. Some patients in this family have pronounced sensory disturbances leading to poorly healing ulcerations.
These unusual sensory signs for CMT were also noted in the only other CMT2B family reported so far, suggesting a distinct clinical phenotype for CMT2B. Exclusion of the locus for hereditary sensory neuropathy type I (HSN I) on chromosome 9q22 indicates that HSN I with mild motor symptoms and CMT2 with prominent sensory abnormalities are not allelic.
2型夏科-马里-图斯病（CMT2）或遗传性运动和感觉神经病II型（HMSN II）是一种遗传性周围神经系统轴索性神经病。三个常染色体显性CMT2基因座已定位在1号染色体的1p35 - p36（CMT2A）、3号染色体的3q13 - q22（CMT2B）和7号染色体的7p14（CMT2D）上，这表明CMT2是一种基因异质性疾病。
利用短串联重复多态性对一个CMT2家系进行与CMT2A、CMT2B和CMT2D基因座的连锁分析。
发现与3q13 - q22连锁的提示性证据。在标记D3S1769和D3S1267处发生了重组，表明CMT2B基因座位于D3S1267的远端，位于一个25厘摩的区间内。该家系中的一些患者有明显的感觉障碍，导致溃疡愈合不良。
在迄今为止报道的另一个唯一的CMT2B家系中也注意到了这些CMT不寻常的感觉体征，提示CMT2B有独特的临床表型。排除9号染色体上I型遗传性感觉神经病（HSN I）的基因座表明，伴有轻度运动症状的HSN I和伴有明显感觉异常的CMT2不是等位基因。
