Neumann Luitgard M, von Moers Arpad, Kunze Jürgen, Blankenstein Oliver, Marquardt Thorsten
Institute of Human Genetics, Charité Campus Virchow-Klinikum, Augustenburger Platz 1, 13353 Berlin, Germany.
Eur J Pediatr. 2003 Oct;162(10):710-3. doi: 10.1007/s00431-003-1278-8. Epub 2003 Aug 2.
We report on a 16-month-old boy with congenital disorder of glycosylation type 1a (CDG-1a; OMIM 212065) showing an atypical phenotype. Whereas failure to thrive is known to be a prominent feature in this condition, our patient developed postnatal macrosomia with increase of weight, length and occipitofrontal circumference (OFC) above the 95th percentile within his 1st year of life. Thereafter, weight and length were close to the 90th and OFC at the 50th percentiles. In contrast to other CDG-1a patients, the child did not have abnormal fat pads or inverted nipples; but unusual eyebrows were present. CDG-1a was confirmed by isoelectric focusing of serum transferrin and measurement of phosphomannomutase activity in leucocytes and cultured fibroblasts (residual activity <5% of controls). Mutation analysis of the phosphomannomutase 2 gene (PMM2) revealed homozygosity for a 647A>T (N216I) mutation in our patient and heterozygosity in his consanguineous parents.
This is the first report of macrosomia and of homozygosity for the 647A>T (N216I) mutation in a patient with congenital disorder of glycosylation type 1a which may allow further phenotype/genotype comparisons.
我们报告了一名患有1a型糖基化先天性疾病（CDG-1a；OMIM 212065）的16个月大男孩，其表现出非典型表型。虽然生长发育迟缓是这种疾病的一个突出特征，但我们的患者出生后出现巨大儿，在其1岁内体重、身长和枕额周长（OFC）增加至第95百分位数以上。此后，体重和身长接近第90百分位数，OFC处于第50百分位数。与其他CDG-1a患者不同，该患儿没有异常脂肪垫或乳头内陷；但有异常的眉毛。通过血清转铁蛋白等电聚焦以及白细胞和成纤维细胞培养物中磷酸甘露糖变位酶活性的测定（残余活性<对照的5%）确诊为CDG-1a。磷酸甘露糖变位酶2基因（PMM2）的突变分析显示，我们的患者为647A>T（N216I）突变纯合子，其近亲父母为杂合子。
这是关于1a型糖基化先天性疾病患者出现巨大儿以及647A>T（N216I）突变纯合子的首例报告，这可能有助于进一步进行表型/基因型比较。
