Clinical manifestations and gene analysis of Hutchinson-Gilford progeria syndrome:A case report

BACKGROUND This case report describes a child with Hutchinson-Gilford progeria syndrome(HGPS,OMIM:176670)caused by LMNA(OMIM:150330)gene mutation,and we have previously analyzed the clinical manifestations and imaging characteristics of this case.After 1-year treatment and follow-up,we focus on analyzing the changes in the clinical manifestations and genetic diagnosis of the patient.CASE SUMMARY In April 2020,a 2-year-old boy with HGPS was found to have an abnormal appearance,and growth and development lagged behind those of children of the same age.The child’s weight did not increase normally,the veins of the head were clearly visible,and he had shallow skin color and sparse yellow hair.Peripheral blood DNA samples obtained from the patient and his parents were sequenced using high-throughput whole-exosome sequencing,which was verified by Sanger sequencing.The results showed that there was a synonymous heterozygous mutation of C.1824 C>T(P.G608G)in the LMNA gene.CONCLUSION Mutation of the LMNA gene provides a molecular basis for diagnosis of HGPS and genetic counseling of the family.

VARS2 gene mutation leading to overall developmental delay in a child with epilepsy: A case report

BACKGROUND The mitochondrial respiratory chain defects have become the most common cause of neurometabolic disorders in children and adults,which can occur at any time in life,often associated with neurological dysfunction,and lead to chronic disability and premature death.Approximately one-third of patients with mitochondrial disease have biochemical defects involving multiple respiratory chain complexes,suggesting defects in protein synthesis within the mitochondria.We here report a child with VARS2 gene mutations causing mitochondrial disease.CASE SUMMARY A girl,aged 3 years and 4 mo,had been unable to sit and crawl alone since birth,with obvious seizures and microcephaly.Brain magnetic resonance imaging showed symmetrical,flaky,long T1-weighted and low T2-weighted signals in the posterior part of the bilateral putamen with a high signal shadow.T2 fluidattenuated inversion recovery imaging showed a slightly high signal and diffusion-weighted imaging showed an obvious high signal.Whole-exome gene sequencing revealed a compound heterozygous mutation in the VARS2 gene,c.1163(exon11)C>T and c.1940(exon20)C>T,which was derived from the parents.The child was diagnosed with combined oxidative phosphorylation deficiency type 20.CONCLUSION In this patient,mitochondrial disorders including Leigh syndrome and MELAS syndrome(mitochondrial myopathy,encephalopathy,lactic acidosis,and stroke-like episodes)were ruled out,and combined oxidative phosphorylation deficiency type 20 was diagnosed,expanding the phenotypic spectrum of the disease.

Clustering for Bivariate Functional Data

In this paper,we consider the clustering of bivariate functional data where each random surface consists of a set of curves recorded repeatedly for each subject.The k-centres surface clustering method based on marginal functional principal component analysis is proposed for the bivariate functional data,and a novel clustering criterion is presented where both the random surface and its partial derivative function in two directions are considered.In addition,we also consider two other clustering methods,k-centres surface clustering methods based on product functional principal component analysis or double functional principal component analysis.Simulation results indicate that the proposed methods have a nice performance in terms of both the correct classification rate and the adjusted rand index.The approaches are further illustrated through empirical analysis of human mortality data.

Two-sample Testing for Mean Functions with Incompletely Observed Functional Data

In functional data analysis,the collected data are often assumed to be fully observed on the domain.However,in dealing with real data(for example,environmental pollution data),we are often faced with the scenario that some functional data are fully observed on dense lattice while others are incompletely observed.In this paper,we propose a method for testing equivalence of mean functions of two samples under this scenario.Some asymptotic results of the proposed methods are established.The proposed test is employed to analyze an environmental pollution study in Liuzhou City of China.Simulations show that the proposed test has a good control of the type-I error,and is more powerful than the complete case test in most cases.

Mallows Model Averaging Estimation for Linear Regression Model with Right Censored Data

This paper is concerned with an optimal model averaging estimation for linear regression model with right censored data. The weights for model averaging are picked up via minimizing the Mallows criterion. Under some mild conditions, it is shown that the identified weights possess the property of asymptotic optimality, that is,the model averaging estimator corresponding to these weights achieves the lowest squared error asymptotically.Some numerical studies are conducted to evaluate the finite-sample performance of our method and make comparisons with its intuitive competitors, while an application to the PBC dataset is provided to serve as an illustration.