Mutation analysis of the PNPLA1 gene in three families with congenital ichthyosiform erythroderma / 中华皮肤科杂志

Objective:To detect gene mutations in 3 Chinese families with congenital ichthyosiform erythroderma.Methods:Exome sequencing of peripheral blood DNA was performed for 3 probands clinically diagnosed with congenital ichthyosiform erythroderma by using a gene panel targeting hereditary skin diseases to identify mutation sites. Primers were designed according to the mutation sites for PCR amplification, and Sanger sequencing was performed to verify the mutations in probands and other family members in order to identify the cause of the disease.Results:The probands 1 and 2 presented with generalized skin dryness and scaling, and polygonal dark brown scales on the extensor aspect of the lower limbs; the proband 3 mainly presented with well-circumscribed erythema, papules and scales scattered on the trunk and extremities. All probands denied family history of similar diseases. Genetic testing showed that the proband 1 carried compound heterozygous mutations c.100G>A and c.377G>A in the PNPLA1 gene, which were inherited from her mother and father respectively; the proband 2 carried compound heterozygous mutations c.320T>A and c.434T>C in the PNPLA1 gene, which were inherited from her mother and father respectively; a homozygous mutation c.1300delG was identified in the PNPLA1 gene in the proband 3. The mutations co-segregated with the disease phenotypes in the two families with compound heterozygous mutations. Among the 5 identified mutations, the two missense mutations (c.377G>A and c.320T>A) were firstly reported.Conclusion:Biallelic mutations in the PNPLA1 gene are the causative mutations responsible for autosomal recessive congenital ichthyosis in the three probands, and the newly reported mutations expand the mutation spectrum in the disease.

Chanarin-Dorfman syndrome: the first case reported in China / 中华皮肤科杂志

Objective:To detect gene mutations and make a diagnosis in a family with ichthyosis accompanied by liver injury.Methods:Clinical data were collected from the proband, and genomic DNA was extracted from peripheral blood samples from the proband and his parents. Exome sequencing was performed in the proband by using a gene panel targeting hereditary skin diseases to identify mutation sites, and then the candidate mutation site was verified by PCR and Sanger sequencing in the family members. Results of peripheral blood smear examination and other auxiliary examinations were collected from the proband and his parents and analyzed.Results:The proband presented with generalized dry skin and tiny white scales on the lower limbs, accompanied by elevated transaminase levels, mild sensorineural hearing loss in both ears and fatty liver. Exome sequencing revealed a homozygous mutation c.933dupA in exon 6 of the ABHD5 gene encoding CGI-58 protein in the peripheral blood genomic DNA of the proband, resulting in a frameshift mutation p.R312Tfs*45 in the amino acid sequence. Heterozygous mutations at this site were identified in his father and mother. The mutation cosegregated with the disease phenotype in the family. The peripheral blood smear examination of the proband showed lipid vacuoles in neutrophils, which were called Jordan anomaly. Conclusion:The diagnosis of Chanarin-Dorfman syndrome was made in the proband based on the presentation of ichthyosis-like skin lesions and abnormal liver function, as well as the homozygous mutation in the ABHD5 gene and Jordan anomaly in peripheral blood smears.

Analysis of keratin 1 gene mutation and phenotypes in a pair of twins with bullous congenital ichthyosiform erythroderma / 中华皮肤科杂志

Objective To identify mutations in keratin genes (KRT1 and KRT10) in a pair of twins with bullous congenital ichthyosiform erythroderma (BCIE),and to explore the relationship between the causative genes and phenotypes.Methods Clinical data were collected from a pair of twins with BCIE and their family members.Peripheral blood samples were obtained from the twins,their old brother and parents,and DNA was extracted from these blood samples.Polymerase chain reaction (PCR)was performed to amplify all the coding exons and their flanking sequences of the KRT1 and KRT10 genes,and 100 unrelated healthy persons served as controls.Results The 11-year-old male proband presented with recurrent blisters,hypertrophy and desquamation all over the body for 11 years.His twin brother had similar skin lesions.Skin examination of the proband showed diffuse erythema covered with thick scaly crusts on the trunk and extremities.Blisters,bullae and erosions due to ruptured blisters were observed locally with tenderness on palpation.There were obvious hyperkeratotic and hard lesions on the big joints of the extremities.Diffuse hyperkeratosis could be seen on the palms and soles.A mutation c.591 + 1G ＞ A was identified at position 1 in intron 1 of the KRT1 gene in the twins,but not in the 3 healthy family members or the 100 unrelated healthy controls.Conclusion The mutation c.591 + 1G ＞ A at position 1 in intron 1 of the KRT1 gene may contribute to the clinical phenotype of the twins with BCIE.

Cisto ductal de glândula lacrimal em paciente com eritrodermia ictiosiforme congênita / Ductal cyst of lacrimal gland in patient with congenital ichthyosiform erythroderma

Resumo A ictiose lamelar é uma doença congênita de herança autossômica recessiva que se caracteriza clinicamente por descamação de toda a superfície corporal devido hiperceratose mucocutânea que pode levar a comprometimento oftalmológico. Neste estudo relatamos um caso de cisto ductal de glândula lacrimal em paciente portador de ictiose lamelar atendido no Hospital Oftalmológico de Anápolis.

Abstract Lamellar ichthyosis is a congenital disease autosomal recessive which is characterized clinically by peeling of all the body surface due hyperkeratosis mucocutaneous that can cause ocular involvement. We reported a case of ductal cyst of the lacrimal gland in patient with lamellar ichthyosis attended in the Ophthalmological Hospital of Anápolis.