常染色体隐性遗传性羊毛状发家系调查及LIPH基因突变分析

目的:检测1例常染色体隐性遗传性羊毛状发患者家系中LIPH和LPAR6基因的突变情况。方法:收集患者临床资料,提取先证者及其家庭成员外周血DNA,采用聚合酶链反应(PCR)法扩增LIPH和LPAR6基因编码区的全部外显子及其侧翼序列并测序。检索文献并总结已有报道的LIPH基因突变位点和临床表现。结果:基因检测发现先证者及其患病弟弟的LIPH基因均发生c.742CA纯合突变,导致氨基酸出现p.His248Asn改变,其父母均为c.742CA杂合突变。结论:在1例常染色体隐性遗传性羊毛状发患者中检测到LIPH基因c.742CA(p.His248Asn)纯合突变,扩展了常染色体隐性遗传性羊毛状发的基因型和临床表型。     

常染色体隐性遗传性羊毛状发伴少毛症两家系基因突变分析

目的:检测常染色体隐性遗传性羊毛状发伴少毛患者家系的致病基因。方法:收集2例中国汉族常染色体隐性遗传性羊毛状发伴少毛家系患者及其父母外周血标本,应用二代皮肤靶向测序包检测血样中DNA的基因突变,Sanger测序进行家系验证,Minigene验证剪切突变致病性。结果:先证者1的LIPH基因检测到c.742C>A(p.His248Asn)和c.982+12A>G的复合杂合突变。先证者2的LIPH基因检测到c.629-1＿629delinsTT和c.686delAinsGTAGAACCCAACCTGGCT的复合杂合突变。一代测序验证显示复合杂合突变分别来自母亲和父亲。LIPH c.982+12A>G和c.629-1＿629delinsTT尚未报道过,Minigene验证发现,剪切突变c.982+12A>G会导致内含子滞留;剪切突变c.629-1＿629delinsTT会导致外显子跳跃和外显子缺失。结论:本文报道了LIPH的两个新剪切突变,通过家系验证和Minigene验证了剪切突变的致病性,丰富了LIPH导致常染色体隐性羊毛状发伴少毛的突变谱。     

常染色体隐性遗传性羊毛状发1例及基因突变研究

目的:分析1例羊毛状发患儿及其父母的基因突变。方法:收集羊毛状发患儿及其父母外周静脉血,提取DNA,同时收集100例非家系健康汉族人DNA作为对照。采用聚合酶链式反应(PCR)法扩增LPAR6、LIPH、KRT25、KRT7及KRT7基因所有外显子,并对其产物进行测序分析。结果:该例患儿未发现LPAR6、KRT25、KRT7及KRT基因突变,LIPH基因存在3处杂合突变。突变1为错义突变c.973CT,突变2为错义突变c.614AG,突变3为错义突变c.454GA。对患儿父母的基因分析表明突变1及突变2均来自其父亲,而突变3来自其母亲。健康对照组中均未发现该杂合突变。结论:LIPH基因的复合杂合突变c.614AG及c.454GA导致该常染色体隐性遗传羊毛状发家系的临床表型,c973CT可能为LIPH基因编码区一新的单核苷酸多态性(SNP)。     

遗传性对称性色素异常症2个新的致病基因突变检测

目的检测遗传性对称性色素异常症2家系中DSRAD基因的突变。方法收集陕西籍遗传性对称性色素异常症2个家系成员资料,提取外周血DNA,PCR扩增DSRAD基因的全部外显子,进行DNA测序,并以50例无关正常人作为对照。结果家系Ⅰ所有患者中8号外显子检测到一新的c.2858C>G(p.S886R)错义突变;家系Ⅱ所有患者中10号外显子检测到一新的c.3073A>G(p.H958R)错义突变。结论DSRAD基因的c.2858C>G和c.3073A>G错义突变可能为引起这两个家系患者临床表型的病因。     

遗传性对称性色素异常症三家系ADAR1基因突变检测

【摘要】 目的 探讨3个遗传性对称性色素异常症家系中ADAR1基因的突变情况。方法 收集血样,用PCR结合DNA直接测序的方法,检测3个家系中的患者、患者亲属及与家系无关的50例健康个体的ADAR1基因突变情况。 结果 所研究的3个家系中均存在ADAR1基因的异常。包括A及C家系中2个错义突变（c.1760A > G导致p.Y587C,c.3620G > T导致p.G1207V）,B家系中1个移码突变（c.2433-2434delAG）。3个家系中未患病个体和健康对照均未发现相应突变。 结论 3个ADAR1基因突变中,2个错义突变均为新突变,可能是导致遗传性对称性色素异常症发病的分子机制之一。     

q遗传性秃发／少毛症分子遗传学研究进展

遗传性秃发／少毛症是一组临床少见的遗传性脱发性疾病。近年确定多种遗传性秃发／少毛症的致病基因及其染色体定位,包括Marie—Unna型遗传性少毛症（U2HR,8p21．3）、常染色体显性遗传性单纯性少毛症（APCDDl,18p11．22;RPL21,13q12）、常染色体隐胜遗传性单纯性少毛症（DSG4,18q12．1;DSC3,18q21．1;LIPH,3q26—27;P2RY5,13q13—14;10q11．23—22．3;7p21．3-22-3）、常染色体隐陛遗传性羊毛状发（LIPH,3q26—27;P2RY5,13q13—14）、常染色体显性遗传性羊毛状发（KRT74,12q12—14）和毛囊性鱼鳞病一秃发一畏光综合征（MBTPS2,Xp22）。这些基因在毛囊发生和毛囊生长周期过程中具有重要的调控作用,各种致病性突变均可导致毛囊发生和生长异常,引起秃发／少毛症。     

汗孔角化症三例散发患者基因突变分析

目的:检测3例散发汗孔角化症患者的致病基因突变。方法:提取3例患者外周血进行基因组DNA提取，通过高通量测序检测患者的突变基因，再用Sanger测序验证。结果:3例汗孔角化症均存在MVD基因突变，患者1检测到c.875A>G(p.Asn292Ser)突变，患者2、3检测到(c.746 T>C)(p.Phe249Ser)突变。结论:本研究再次验证MVD基因为汗孔角化症常见突变。     

眼皮肤白化病1家系致病基因鉴定

【摘要】 目的 利用全外显子测序及Sanger测序技术对两兄弟眼皮肤白化病患者的（OCA）家系进行致病基因筛选和鉴定。方法 收集1个OCA家系的临床资料，提取家系成员的外周血DNA，通过全外显子组测序技术对先证者的全外显子编码区进行直接测序以寻找可能存在的基因突变，并利用Sanger测序进行一代验证。结果 先证者及其弟弟均表现为全身皮肤、毛发变白，双眼球震颤，畏光，虹膜半透明，结膜充血，双眼屈光不正。先证者父母、祖父母、外祖父母及子女表型均正常，父母非近亲结婚。两兄弟OCA2基因中均出现3个杂合变异，即c.1290T>A无义突变、c.1363A>G错义突变和c.1204T>C错义突变。其中，OCA2 c.1204T>C尚未有报道，为OCA2基因的新突变位点。此外，先证者父亲OCA2基因存在杂合变异c.1204T>C；先证者母亲OCA2基因存在杂合变异c.1290T>A及c.1363A>G；先证者儿子OCA2基因存在杂合变异c.1290T>A；先证者女儿OCA2基因存在杂合变异c.1204T>C，先证者弟弟的女儿OCA2基因存在杂合变异c.1290T>A。结论 本研究中2例OCA2患者均出现3处OCA2基因突变，其中c.1290T>A无义突变可能是导致该家系临床表型的突变位点，这些发现丰富了OCA2的致病基因突变谱。     

二例遗传性大疱性表皮松解症基因突变研究

目的:检测分析2例遗传性大疱性表皮松解症患者致病基因及突变位点。方法:收集患者资料,提取患者及父母外周血DNA,利用全基因组外显子测序筛查致病基因,经生物信息学分析获得致病变异;随后用Sanger测序在患者及其亲属中验证该突变。结果:患者1父母表型正常,患者2父亲有相似临床表现。患者1携带COL7A1基因73号外显子c.6082G>A(p.G2028R)的错义突变,其父母未发现该突变。患者2及其父亲携带2个致病的错义突变,即COL7A1基因c.6235G>A(p.G2079R)突变和KRT5基因c.499G>A(p.E167K)突变,其母未发现该突变。结论:散发患者存在的COL7A1基因突变属于新生突变;患者2及其父亲同时携带COL7A1基因和KRT5基因的杂合错义突变,为国内外首次报道。     

表皮松解性掌跖角化病一家系KRT9基因突变检测

目的：检测一表皮松解性掌跖角化病(epidermolytic palmoplantar keratoderma,EPPK)家系中患者及其家族成员的KRT9基因突变。方法：收集该EPPK家系先证者及其家族成员临床资料,提取他们及100例无亲缘关系的健康对照外周血DNA,PCR扩增KRT9基因编码区的全部外显子及其侧翼序列,对产物直接测序,同时进行突变点的功能预测。结果：该家系所有患者的KRT9基因1号外显子第482位碱基均发生错义突变c.482A>G(p.Asn161Ser)。家系中未患病者及100名正常对照中均未发现此突变。SIFT和Polyphen-2软件预测c.482A>G(p.Asn161Ser)突变为有害变异位点。结论：KRT9基因的突变c.482A>G(p.Asn161Ser)可能是导致该家系发生表皮松解性掌跖角化病的原因。     

Identification of 736T>A mutation of lipase H in Japanese siblings with autosomal recessive woolly hair

Woolly hair is characterized by fine and tightly curled hair. It has recently been revealed that both LPAR6 and lipase H (LIPH) mutations cause autosomal recessive woolly hair (ARWH)/hypotrichosis. This notion has provided critical evidence to the concept that LPA6 activation by LIPH-catalyzed lipid mediator lysophosphatidic acid has a key role in regulation of hair follicle development. Very recently, novel mutations in exon 6, homozygous 736T>A and compound heterozygous 736T>A and 742C>A have been identified in Japanese ARWH/hypotrichosis patients. Here, we report on siblings (a 7-year-old Japanese girl and her 5-year-old brother) both showing woolly hair. Determination of their genomic sequence showed presence of a homozygous 736T>A transition in exon 6 of the LIPH gene changing cysteine at position 246 to serine, without any mutation in the LPAR6 gene. Additionally, the same mutation was found in one out of a 100 alleles of Japanese healthy controls and identified homozygously in three out of four other Japanese sporadic cases with woolly hair. Collectively, it has been suggested that 736T>A transition is highly specific and common in ARWH/hypotrichosis of Japanese origin.     

Prevalent founder mutation c.736T>A of LIPH in autosomal recessive woolly hair of Japanese leads to variable severity of hypotrichosis in adulthood

Background Mutations in LIPH are a cause of autosomal recessive woolly hair (ARWH). Homozygous c.736T>A (p.Cys246Ser), and compound heterozygous c.736T>A and c.742C>A (p.His248Asn) have been reported in 5 and 7 Japanese children with ARWH respectively. The severity of hypotrichosis is known to be able to change in the clinical course, and the mutation patterns of LIPH do not always correlate with the severity of hypotrichosis in ARWH caused by other mutation sites of LIPH. However, all 12 Japanese children previously reported to have ARWH have shown similar severity of hypotrichosis. Objective In this study, we investigated the clinical features and molecular basis of ARWH in patients including three adults (three adults and two children) from five non‐related Japanese families. Methods Five families of Japanese origin that presented with woolly hair were studied. The phenotype was confirmed by clinical examination. Direct automated DNA sequencing of the LIPH gene was performed to identify the mutations in our probands. Results All patients had had woolly hair since birth. Homozygous c.736T>A mutations were found in four patients, including three adult cases, and compound heterozygous c.736T>A and c.742C>A mutations were found in one child patient. The two adults and two children had only sparse scalp hair, although one adult woman had mild hypotrichosis with long hairs. Conclusion Some patients with homozygous c.736T>A can have a mild hypotrichosis phenotype with long hairs in adulthood.     

A Missense Mutation within the Helix Initiation Motif of the Keratin K71 Gene Underlies Autosomal Dominant Woolly Hair/Hypotrichosis

Woolly hair (WH) is an abnormal variant of tightly curled hair, which is frequently associated with hypotrichosis. Non-syndromic forms of WH can show either autosomal-dominant WH (ADWH) or autosomal-recessive WH (ARWH) inheritance patterns. ARWH has recently been shown to be caused by mutations in either the lysophosphatidic acid receptor 6 (LPAR6) or lipase H (LIPH) gene. More recently, a mutation in the keratin K74 (KRT74) gene has been reported to underlie ADWH. Importantly, all of these genes are abundantly expressed in the inner root sheath (IRS) of human hair follicles. Besides these findings, the molecular mechanisms underlying hereditary WH have not been fully disclosed. In this study, we identified a Japanese family with ADWH and associated hypotrichosis. After exclusion of known causative genes, we discovered the heterozygous mutation c.422T>G (p.Phe141Cys) within the helix initiation motif of the IRS-specific keratin K71 (KRT71) gene in affected family members. We demonstrated that the mutant K71 protein led to disruption of keratin intermediate filament formation in cultured cells. To our knowledge, it is previously unreported that the KRT71 mutation is associated with a hereditary hair disorder in humans. Our findings further underscore the crucial role of the IRS-specific keratins in hair follicle development and hair growth in humans.     

Novel small-insertion mutation in the LIPH gene in a patient with autosomal recessive woolly hair/hypotrichosis

Autosomal recessive woolly hair/hypotrichosis (ARWH/H) is a rare form of congenital alopecia, which can be caused by mutations in lipase H (LIPH), lysophosphatidic acid receptor 6 (LPAR6/P2RY5) or keratin 25 (KRT25) genes. We present a 32-year-old woman with typical clinical features of ARWH. Hair microscopy was performed to observe differences between the patient’s hair and a normal sample. Next-generation sequencing was used to detect pathogenic mutations. Sanger sequencing was used to further confirm the mutations. Abnormal hair appearance was found by hair microscopy. A novel frame-shift mutation (NM_139248: c.686delinsGTAGAACCCAACCTGGCT: p.Asp229fs37X) and a reported mutation (NM_139248: exon6:c.T736A: p.C246S) in LIPH were identified in the patient. All reported mutations related to ARWH of various races were reviewed. Our study provides further evidence of the similarity of ARWH between the Chinese and Japanese population. A novel small-insertion mutation also expands the LIPH mutation spectrum.     

Phenotypic diversity of the recurrent p.Val379Leu missense mutation of the TGM1 gene

Autosomal recessive congenital ichthyosis type 1 (ARCI1), a clinically heterogeneous group of keratinization disorders, develops due to mutations in the transglutaminase 1 (TGM1) gene. Here we report a Hungarian pedigree affected by the lamellar ichthyosis clinical form of the ARCI1 phenotype. Direct sequencing revealed two recurrent heterozygous mutations: a splice site (c.877-2A > G) and a missense (c.1135G > C, p.Val379Leu) mutation. This splice site mutation is the most frequently observed in ARCI1 worldwide. The missense mutation is relatively rare and has been reported in only 13 Scandinavian patients. Comparison of the clinical phenotypes of our Hungarian patients and the Scandinavian patients demonstrates great phenotypic diversity associated with the p.Val379Leu genotype.     

Mutations in mevalonate pathway genes in patients with familial or sporadic porokeratosis

Porokeratosis comprises heterogeneous keratinization disorders that are characterized by one or more atrophic patches surrounded by a ridge‐like cornoid lamella. In this study, we evaluated seven families affected by porokeratosis and five sporadic patients of the disease in a Chinese population. We performed Sanger sequencing of exons and flanking intron–exon boundaries of mevalonate pathway genes (MVD, MVK, PMVK and FDPS) and of SLC17A9. In five familial and three sporadic patients, we detected six variations, including four novel mutations (MVD c.1A>G; p.Met1?, c.916G>A; p.Ala306Thr, c.1013+1G>A, and PMVK c.65A>G; p.Lys22Arg) and two recurrent mutations (MVD c.746T>C; p.Phe249Ser, and MVK c.1028T>C; p.Leu343Pro). We then applied I‐TASSER and iGEMDOCK to assess these variants for probable functional impacts. The findings of this study extend the mutation spectrum of porokeratosis and provide further evidence for the genetic basis of this disease.     

IL36RN基因突变与掌跖脓疱病的相关性研究

目的：明确IL36RN基因突变与掌跖脓疱病的相关性。方法：提取96例掌跖脓疱病患者(PPP)与144名健康对照外周血DNA,采用聚合酶链反应(PCR)技术扩增 IL36RN 基因所有外显子及其侧翼序列并进行Sanger测序。结果：96例PPP患者中有3例患者携带c.115+6T>C(p.Arg10ArgX1),3例携带c.140A>G (p.Asn47Ser)。144名对照者中有2名携带c.115+6T>C,4名携带c.140A>G。PPP组与健康对照组IL36RN突变率比较,差异无统计学意义(P=0.67,OR=0.65,95% CI: 0.20~2.09)。结论：PPP与IL36RN基因突变不相关。     

Sjogren-Larsson综合征ALDH3A2基因突变研究

目的 检测2例以先天性鱼鳞病、智力发育迟缓及痉挛性截瘫为主要表现的Sj?觟gren-Larsson综合征患者的ALDH3A2基因突变情况。 方法　2例分别为2岁女性及1.5岁男性儿童,家族中均无类似疾病。提取2例患者及其6例相关亲属（每例患儿的父母及哥哥）外周血DNA,采用PCR扩增ALDH3A2基因编码区的全部外显子及其侧翼序列并测序。同时随机抽取100例无关健康人外周血基因组DNA作对照。结果基因检测发现,例1的ALDH3A2基因发生c.325G>A纯合突变,导致氨基酸出现p. Gly109Arg改变,其父母及其未受累的兄长为该突变的杂合携带者。例2的ALDH3A2基因发生c.1157A>G及c.1294A>T复合杂合突变,导致氨基酸出现p. Asn386Ser及p.Arg432X改变,突变分别来自父母。100例健康对照者均未见相同突变。结论 在2例Sj?觟gren-Larsson综合征患者中检测到ALDH3A2基因的p. Gly109Arg纯合突变及p. Asn386Ser与p. Arg432X复合杂合突变,该基因突变可能与患者临床表型相关。 【关键词】 Sjogren-Larsson综合征; 鱼鳞病; 突变; ALDH3A2