Clinical and Genetic Study of Children With Peutz-Jeghers Syndrome Identifies a High Frequency of STK11 De Novo Mutation.

OBJECTIVES: The present study aims to identify the genotype-phenotype correlation in children with Peutz-Jeghers Syndrome (PJS) through the analysis of STK11 gene mutations in the context of clinical and pathological characteristics. METHOD: In this observational cohort study, the clinical characteristics of 18 families diagnosed with pediatric PJS were collected. Genomic DNA from the peripheral blood of affected children and their family members was collected. The coding region of STK11 was amplified by PCR and screened for mutation by Sanger sequencing. The families that were negative for STK11 mutation were further assessed by multiplex ligation-dependent probe amplification (MLPA). RESULT: Initial presentation in affected children was at 1.6 to 14.2 years and included anemia in 8 patients whereas 6 presented for screening by virtue of family history. All patients underwent endoscopy, colonoscopy, and polypectomy. Polyps were distributed throughout the gastrointestinal (GI) tract, including the small intestine, stomach, colon, and rectum.In the 18 pediatric PJS families, STK11 mutations were detected in 8 families by Sanger sequencing, and large deletions were detected in 3 by MLPA, respectively. Nine of the 11 STK11 mutations were de novo, 3 were novel (c.419T>C:p.L140P, c.314T>G:p.L105X), and (c.488_489insACGG p.L164fs). CONCLUSIONS: Although the main clinical features of pediatric PJS were similar to those of PJS cases in adults, a high frequency of STK11 de novo mutations were encountered in our population of patients with PJS.

Trisomy 3 mosaicism in a 5-year-old boy with multiple anomalies: A very rare case.

Trisomy 3 mosaicism in live birth is exceedingly rare. In this study, we report a 5-year-old boy with trisomy 3 mosaicism who exhibits skeletal anomalies, atypical form of ectodermal dysplasias, refractory diarrhea, and normal intelligence. Fluorescence in situ hybridization and microsatellite marker analyses confirmed the existence of trisomy 3 mosaicism and suggested that the parental origin of the additional chromosome 3 in the trisomic cells was maternal. This report further delineated the trisomy 3 mosaicism in live births. The authors propose that both common phenotypes and phenotypic diversity exist on cases with trisomy 3 mosaicism. © 2016 Wiley Periodicals, Inc.

First report of CTNS mutations in a Chinese family with infantile cystinosis.

Infantile cystinosis (IC) is a rare autosomal recessive disorder characterized by a defect in the lysosomal-membrane transport protein, cystinosin. It serves as a prototype for lysosomal transport disorders. To date, several CTNS mutations have been identified as the cause of the prototypic disease across different ethnic populations worldwide. However, in Asia, the CTNS mutation is very rarely reported. For the Chinese population, no literature on CTNS mutation screening for IC is available to date. In this paper, by using the whole exome sequencing and Sanger sequencing, we identified two novel CTNS splicing deletions in a Chinese IC family, one at the donor site of exon 6 of CTNS (IVS6+1, del G) and the other at the acceptor site of exon 8 (IVS8-1, del GT). These data give information for the genetic counseling of the IC that occurred in Chinese population.

Interstitial deletion 5q14.3q21.3 associated with lethal epilepsy.

The 5q14.3 deletion syndrome is a heterogeneous disorder with remarkable phenotypic diversity ranging from severe to mild manifestation. In this paper, we report on a patient with 5q14.3 q21.3 deletion who exhibited the severe phenotype and died at 5.5 months. This patient can be classified as having sudden unexplained death in epilepsy (SUDEP) [Tomson et al., 2008]. The deleted region (21.02 Mb, Chr.5: 88, 047, 621-109,072,596 × 1 dn), which included MEF2C and EFNA5, was a 16.5 Mb sequence that overlapped with previously reported deletions in a patient with the mild phenotype. This study further demonstrated the complexity of clinical cytogenetic correlation of the 5q14.3 deletion.

A novel splicing mutation of KIT results in piebaldism and auburn hair color in a Chinese family.

Piebaldism is a rare autosomal dominant disorder of melanocyte development, which is mostly caused by KIT gene. The key characteristics of piebaldism include localized poliosis, congenital leukoderma, and other variable manifestations. The previous study has illustrated that the homogeneous MC1R (a gene which is associated with the hair color) variant (p.I120T) coordinating with KIT mutation may lead to auburn hair color and piebaldism. In this study, we have investigated a Chinese family with piebaldism and auburn hair color; the mutation screening of KIT and MC1R genes identified that only a splicing mutation (c. 2484+1G>A) of KIT gene cosegregated with the auburn hair color and piebaldism. The data of this study and others suggests that the KIT mutation may causes of the auburn hair color in the piebaldism patients.

First report of HGD mutations in a Chinese with alkaptonuria.

Alkaptonuria (AKU) is one of the first prototypic inborn errors in metabolism and the first human disease found to be transmitted via Mendelian autosomal recessive inheritance. It is caused by HGD mutations, which leads to a deficiency in homogentisate 1,2-dioxygenase (HGD) activity. To date, several HGD mutations have been identified as the cause of the prototypic disease across different ethnic populations worldwide. However, in Asia, the HGD mutation is very rarely reported. For the Chinese population, no literature on HGD mutation screening is available to date. In this paper, we describe two novel HGD mutations in a Chinese AKU family, the splicing mutation of IVS7+1G>C, a donor splice site of exon 7, and a missense mutation of F329C in exon 12. The predicted new splicing site of the mutated exon 7 sequence demonstrated a 303bp extension after the mutation site. The F329C mutation most probably disturbed the stability of the conformation of the two loops critical to the Fe(2+) active site of the HGD enzyme.

[A family of congenital fibrosis of extraocular muscles associated with juvenile canities].

OBJECTIVE: To analyze the clinical manifestations of affected individuals in a family of congenital fibrosis of the extraocular muscles (CFEOM) with juvenile canities. METHODS: All affected and unaffected individuals were retrospectively analyzed in this study. The clinical features include genetic aspects, sex, age, ptosis, restriction of eye movement, aberrant innervation and surgical procedures, were evaluated. RESULTS: This pedigree was inherited as autosomal dominant. There were 14 cases suffering from congenital fibrosis of extraocular muscles in four generations. They had congenital blepharoptosis, head-tilt, chin lift and primary gaze fixed in a hypotrophic position. But vertical and horizontal positions of the eye and restriction of eye movement were different among affected individuals. Some of them also had pupillary abnormally, aberrant innervation and juvenile canities. Inferior rectus recession improved hypotropia in patients with infraducted eyes and chin elevation. Horizontal muscle recession corrected horizontal strabismus satisfactorily in most cases. Ptosis was repaired by frontalis sling or levator resection. CONCLUSIONS: This is the first report of CFEOM associated with juvenile canities. There was phenotypic heterogeneity in this CFEOM pedigree. So the phenotype alone is not sufficient to distinguish among the 3 genotypically distinct CFEOM syndromes. The combination of clinical characteristics and genetic analysis are the basis for the establishment of diagnosis.

Subchronic toxicity studies of Radix Astragali extract in rats and dogs.

Radix Astragali extract (RAE) is obtained from Astragalus membranaceus. It consists of Astragalus polysaccharide and Astragalus membranaceus saponins. In the study, we observed the subchronic toxicity of RAE in Sprague-Dawley rats and beagle dogs to evaluate the safety dosage range in clinical application. These subjects were daily administered of RAE by intra-peritoneum or vein for three consecutive months. General index were observed such as food-intake, behavior, body weight, hematological parameters, etc. Body weight, the weight of principal organ and hematology index are normal in experimental groups and control groups. The hematological biochemistry examination and histopathology examination of experimental groups are similar to control groups. In conclusion, our studies clearly demonstrated that RAE was safe without any distinct toxicity and side effects, the safety dosage range is 5.7-39.9g/kg for rats and 2.85-19.95g/kg for beagle dogs, which is equal to 70 or 35 times of that of human (0.57g/kg, say, average BW 70kg), respectively.

[Exclusive gene mapping on retinitis pigmentosa with markers on chromosomes 3 in a Chinese kindred].

OBJECTIVE: To study the relationship between the rhodopsin gene on chromosome 3 and autosomal dominant retinitis pigmentosa (ADRP) in a Chinese kindred. METHODS: Sixteen normal persons and 18 RP patients in a ADRP family were recruited. Genome scan method based on fluorescence labeled (using 3 different labels: 6-FAM, HEX, and NED) microsatellite markers with multiplex PCR system was used to identify loci influencing susceptibility to ADRP. Fourteen microsatellites (D3S1297, D3S1263, D3S1266, D3S1289, D3S1300, D3S3681, D3S1271, D3S1292, D3S1569, D3S1279, D3S1614, D3S1262, D3S1580 and D3S1311) on chromosome 3 were used as genetic markers. Linkage analysis (using Genescan3.0, GeneScan Analysis 2.1, Genotyper 2.1 and Designer sofe system) was performed using these markers. RESULTS: The LOD value was