[Gene mutation analysis of a collodion baby].
OBJECTIVE
To determine the mutations pattern of the genes of a collodion baby.


METHODS
Collodion baby is a genetic heterogeneous disease caused by mutations of several genes. Since the most common mutations were observed in TGM1 gene, this gene was chosen for mutation screening. The screening was carried out by PCR and direct sequencing. The allele specific primers were designed for a missense mutation and allele-specific (AS) PCR was carried out in 50 normal individuals for population study.


RESULTS
Three novel alterations were detected in TGM1 gene of the proband, a missense mutation c.463C > T (p.Arg155Trp) in exon 3, a nonsense mutation c.578G > A (p.Trp193X) in exon 4, and a single nucleotide deletion (c.694delG) also in exon 4 of TGM1 gene. This infant's father was heterozygote of c.694delG mutation, while his mother carried the two mutations (c.463C > T and c.578G > A) on the same chromosome. The missense mutation was not detected in his father and in any of the control individuals by AS-PCR.


CONCLUSIONS
Three novel mutations were identified in TGM1 gene in a Chinese collodion baby. A double mutation (c.463C > T and c.578G > A) located on the maternal allele while the c.694delG deletion on the paternal allele.
Dian
Yan
Y
Department of Medical Genetics, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, WHO Collaborating Centre for Community Control of Hereditary Diseases, Beijing 100005, China.
Meng
Yan
Y
Wang
Zheng
Z
Peng
Yuan-yuan
YY
Zhou
Qing
Q
Li
Xiao-qiao
XQ
Su
Liang
L
Huang
Shang-zhi
SZ
D000483:Alleles; D004252:DNA Mutational Analysis; D005091:Exons; D005808:Genes, Recessive; D005820:Genetic Testing; D006801:Humans; D017490:Ichthyosis, Lamellar / Q000235:genetics*; D008297:Male; D017354:Point Mutation; D016133:Polymerase Chain Reaction; D017421:Sequence Analysis; D017384:Sequence Deletion