Retinopathy of prematurity: Mutations in the Norrie disease gene and the risk of progression to advanced stages

BACKGROUND: Retinopathy of prematurity (ROP) is a retinal vascular disease that occurs in infants with short gestational age and low birth weight and may lead to retinal detachment and blindness. Missense mutations in the Norrie disease (ND) gene have been associated with the risk of progression to advanced stages in cases of ROP from the US and also in clinically similar ND and familial exudative vitreoretinopathy. METHODS: We have screened two ND gene mutations, namely A105T and Val60Glu, by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and allele-specific PCR methods, respectively, in 210 Kuwaiti premature newborns to replicate these findings in a different ethnic group. RESULTS: In the Kuwaiti premature newborn cohort, 115 of 210 babies had no eye problems and served as controls, while 95 were cases of ROP. In 71 of 95 ROP cases, the disease regressed spontaneously on or before stage 3, while in 24 of 95 ROP cases the disease progressed to advanced stages 4 and 5. In case of missense mutation (A105T), the AA genotype was detected in 96% of controls compared with 87% of ROP cases (NS); similarly no significant difference was found between spontaneously regressed ROP cases and those who progressed to advanced stages. For the Val60Glu mutation, no significant association was detected between the genotype and progression of ROP to advanced stages. CONCLUSIONS: Unlike data from the US, our findings from a Kuwaiti cohort of ROP cases and controls suggest a lack of association between the two ND gene mutations (A105T and Val60Glu) and ROP and the risk of progression of the disease to advanced stages.     

Angiotensin-converting enzyme gene insertion/deletion polymorphism in Kuwaiti children with retinopathy of prematurity

Retinopathy of prematurity (ROP) is a disease characterized by neovascularization which occurs in infants with short gestational age and low birth weight and can lead to retinal detachment and blindness. In a proportion of ROP cases, the disease progresses to advanced stages despite rigorous intervention. The genotypes for angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism were determined in 181 premature Kuwaiti infants using a polymerase chain reaction (PCR) method. The incidence of different I/D genotypes was compared in ROP cases (n = 74) and non-ROP controls (n = 107) and within 2 subgroups of ROP patients: (1) in which ROP regressed spontaneously (stages 1-3, n = 53), and (2) in which ROP progressed to advanced stages (stages 4 and 5, n = 21). When the ROP cases were considered collectively as one group, the incidence of the DD genotype was almost identical to that of non-ROP controls. The incidence of heterozygous ID genotype was higher in non-ROP controls. The incidence of the II genotype was higher in ROP cases compared to non-ROP controls (p < 0.01). In contrast to this, when ROP cases were divided in 2 subgroups the incidence of the DD genotype was significantly higher in advanced stage ROP cases compared to spontaneously regressing ROP cases (p < 0.04). The incidences of ID and II genotypes were not significantly different amongst the 2 subgroups of ROP patients.     

Macular pigmentary changes as a sequelae of retinal hemorrhages in premature infants with retinopathy of prematurity

PURPOSE: We assess the incidence of macular changes in ROP patients with retinal hemorrhages. PATIENTS AND METHODS: The premature group consisted of 360 children born 32 weeks gestation and/or with weight below 1,500 g. We used the RetCam-120 Digital Retinal Camera to document retinal changes. RESULTS: Of the 360 premature infants 241 (67%) had no ROP, and 119 (33%) had ROP. Of the preterm infants with ROP retinal hemorrhages were found in 46 (38%) children. Of the newborns with ROP and with retinal hemorrhages, macular pigmentary changes were found in 3 (6%) patients. Of these 3 patients, the first had pre-threshold ROP, the second threshold ROP and had underwent diode laser photocoagulation, and the third patient had stage 2 ROP. In the patients with pre-threshold and threshold ROP retinal hemorrhages appeared 6 weeks after birth and macular pigmentary changes were found 6 months after birth. In the patient with stage 2 ROP hemorrhages appeared 7-8 weeks after birth and macular pigmentary changes were detected 12 months after birth. CONCLUSIONS: Although macular hemorrhages almost always resorb without complications, our study allows the assumption that retinal hemorrhages may cause macular pigmentary changes in the macula, and thus may lead to deprivation amblyopia. Our results may suggest that the presence of the macular pigmentary changes may be related to the hemorrhage and not to the specific therapy or to the disease.     

Mutation analysis of phenylketonuria in Yamagata prefecture, Japan

BACKGROUND: We have screened 309,914 newborns in Yamagata prefecture, Japan, since 1977 and have detected four patients with phenylketonuria (PKU). We analyzed the phenylalanine hydroxylase (PAH) gene of the four patients to study the genetic background in this area and the genotype-phenotype relationship in these patients. METHODS: Mutations of the PAH gene were screened by denaturing gradient gel electrophoresis analysis and the sequences were determined. RESULTS: Three cases were compound heterozygotes of six different mutations of the PAH gene and the remaining case was a homozygote. Of the six detected mutations, K115fs is novel, whereas the others have been previously detected among Chinese and/or Japanese patients. CONCLUSIONS: The incidence and genetic basis in Yamagata prefecture was similar to that of other parts of Japan. Analysis of the genotype is useful to understand the clinical variation in some families.     

早产儿视网膜病的高危因素分析

目的了解我院早产儿视网膜病（refinopathy of prematurity,ROP）的发病状况,并对其高危因素进行分析。方法对2010年1月至2012年12月在我院新生儿科住院的早产儿（胎龄≤36周,体重≤2．5kg）,于生后2周进行ROP筛查,并定期随访。将患儿全身状况及吸氧、母孕期吸氧、先兆子痫、胎盘早剥等因素进行分析。结果255例患儿全部完成了眼底筛查,在周边视网膜血管化或病变退化后终止随访,发现ROP16例（26只眼）,ROP患病率为6．3％（5．1％）,其中Ⅰ期12例,Ⅱ期3例,Ⅲ期1例。高危因素分析示胎龄、出生体重、吸氧时间,吸氧浓度、机械通气与ROP相关（P〈0．05）;母孕期吸氧、先兆子痫、胎盘早剥等因素与ROP发病无关。结论早产、吸氧浓度高、机械通气是ROP的主要危险因素。对早产儿适时进行ROP筛查,并对发现的ROP早期进行有效视网膜激光光凝术,可控制病变,降低早产儿的致盲率。     

西北地区751例新生儿耳聋基因突变筛查

目的初步了解西北地区新生儿常见耳聋基因突变类型和携带率,探讨耳聋基因突变筛查对于辅助诊断和防治新生儿遗传性耳聋的临床价值。方法采集西北地区751例新生儿的足跟血,采用15项遗传性耳聋基因检测试剂盒(微阵列芯片法)对中国人群常见4种耳聋基因15个突变位点进行筛查。结果在751例新生儿中,检测到39例新生儿携带耳聋基因突变,总突变携带率为5.18%。其中GJB2基因突变19例,突变携带率为2.53%;SLC26A4基因突变16例,突变携带率为2.12%;线粒体12SrRNA 1555A>G均质突变4例,突变携带率为0.53%。新疆出生的新生儿279例中,检测到耳聋基因突变11例,突变携带率3.95%;甘肃省出生的新生儿277例中,检测到耳聋基因突变12例,突变携带率4.32%;陕西省出生的新生儿178例中,检测到耳聋基因突变12例,突变携带率6.74%;青海省出生的新生儿17例中,检测到耳聋基因突变4例,突变携带率23.52%。结论西北地区新生儿耳聋基因突变携带率偏高,但是GJB2基因235 del C位点的突变携带率偏低,可能与西北地区的地域特征和人口遗传学特点有关。新生儿耳聋基因筛查对于听力筛查具有很好的互补作用,可以从基因水平发现可能出现迟发性耳聋和药物敏感性耳聋的高危新生儿。     

早产儿视网膜病1082例筛查报告及诊治分析

目的 探讨早产儿视网膜病(ROP)的早期诊治方法,分析其筛查结果.方法 由眼底病专科医生应用双目间接眼底镜对本院新生儿科2004年7月至2009年6月收治的胎龄＜34周或出生体质量＜2000 g的住院早产儿进行ROP筛查.首次筛查时间为纠正胎龄32～34周或生后4～6周,对检出的阈值期或阈值前期1型ROP(重症)患儿全部给予眼底激光光凝术,对视网膜血管未发育成熟、1～2期或阈值前期2型(轻度)ROP患儿进行密切随访,直至视网膜血管发育至锯齿缘或发展成为重症.对所有的临床资料进行回顾性分析.结果 5年共收治早产儿2 295例,符合筛查标准的早产儿1 082例,占47.14%;检出ROP总阳性病例154例,占筛查对象的14.23%(154/1082);其轻度ROP86例,占7.94%(86/1 082);重症ROP 68例,占6.28%(68/1 082).68例重症ROP患儿中,有6例出院后随访期间发现进展为重症ROP而再入院,有2例放弃治疗1年后证实全部失明.66例(132只眼)接受各种治疗,其中63例单用光凝术治疗;3例急进性后极ROP中2例采用玻璃体腔内注入血管内皮生长因子拮抗剂(Avastin)联合光凝术治疗,1例单用光凝术治疗者治疗后仍出现部分视网膜脱离,经玻璃体视网膜手术后仍失明;随访结果65例成功的保存了视力,成功率98.48%(65/66).在观察期间未达到光凝治疗条件,因原发病恶化死亡10例,经光凝治疗后的患儿未出现死亡.结论 ROP筛查是防止ROP病情发展的有效措施,对重症ROP及时给予光凝术治疗是安全有效的方法,对急进性后极ROP可用玻璃体腔内注入血管内皮生长因子拮抗剂联合光凝术治疗抢救视力.     

Retinopathy of prematurity in infants < 32 weeks' gestation at birth in New South Wales in 1993 and 1994

OBJECTIVE: To study the incidence and severity of retinopathy of prematurity (ROP) in infants < 32 weeks' gestation. DESIGN: Review of the records maintained in the New South Wales Neonatal Intensive Care Unit Study (NICUS) database on infants admitted to the neonatal intensive care units (NICU) in NSW from 1 January 1993 to 31 December 1994. RESULTS: In the more premature infants, 23-26 weeks' gestation, 65% developed ROP (102 of 157 examined for ROP). Forty-four infants (28%) developed severe ROP (Stage >/= 3 ROP), 19 infants (12.1%) required cryo/laser therapy and one infant (0.6%) in this group had a retinal detachment. One hundred and fifty-seven of 159 surviving infants (98.7%) were examined for ROP. In the infants 27-28 weeks' gestation, 38.3% developed ROP (103 of 269 examined for ROP). Fifteen infants (5.6%) developed severe ROP, seven infants (2. 6%) required cryo/laser therapy for threshold ROP and three infants (1.1%) in this group had a retinal detachment. Two hundred and sixty-nine of 299 surviving infants (90%) were examined for ROP. In the infants 29-31 weeks' gestation, 10.8% developed ROP (48 of 443 examined for ROP). Six infants (1.4%) developed severe ROP, one infant (0.2%) required cryo/laser therapy for threshold ROP and no infant in this group had a retinal detachment. However, only 443 of 681 surviving infants (65.1%) in this group were examined for ROP. Of the four infants with detached retinas, one was a 25 week gestation infant weighing 840 g, two were 27 weeks' gestation weighing 960 and 980 g and one infant was a 28 week gestation infant weighing 620 g. No infant developed Stage 5 ROP. CONCLUSION: In the more mature infants 29-31 weeks' gestation, the rate of ROP is low, although severe ROP still occurs. However, only 65.1% of these infants were examined for ROP and we should be diligent in screening for ROP in the sicker infants in this group. The incidence of severe ROP as well as the rate of cryo/laser therapy in premature infants 23-26 weeks' in NSW has not changed since the increases seen in the early 1990s. Retinal detachment also occurs in the infants 27-28 weeks' gestation and it is important that all these infants are screened for ROP.     

Angiotensin-converting enzyme gene insertion/deletion polymorphism and renal damage in childhood uropathies

BACKGROUND: The activation of the renin-angiotensin system in various renal disorders is well established. Congenital urological abnormalities, such as obstruction and reflux, are common causes of renal failure in children contributing to approximately 25% of chronic renal failure in this age group. While the outlook relates to the severity of initial renal damage, there is considerable heterogeneity in renal parenchymal destruction among individuals and the reasons for this heterogeneity are not fully understood. A polymorphism within intron 16 of the angiostensin-converting enzyme (ACE) gene has been shown to influence the activity of the renin-angiotensin system, thus, it may also have an impact on the expression of renal disorders. We have determined the incidence of this ID polymorphism of the ACE gene in 47 Kuwaiti children with different urological abnormalities leading to variable degrees of renal impairment and in 48 healthy control subjects with a similar ethnic background. METHODS: Blood samples were collected from the patients (n = 47) and controls (n = 48), total genomic DNA extracted and the ACE genotypes were determined using a polymerase chain reaction-based method. RESULTS: The DD genotype was detected in 27/47 (57%) cases compared with 25/48 (52%) controls (P = 0.439). The heterozygous genotype ID was found in 14/47 (29%) cases compared with 22/48 (46%) controls (P = 0.0138). The homozygous II genotype was detected in 6/47 (13%) cases compared with 1/48 (2%) controls (P = 0.0247). The D allele of ACE gene was detected in 41/47 (87%) uropathy cases when individuals with homozygous DD and heterozygous ID genotypes were considered collectively. The incidence of parenchymal damage was considerably higher in uropathy cases with DD genotype (62%) compared with those having ID (26%) and II (12%) genotypes. CONCLUSIONS: Our data suggest an association of D allele of the ACE gene insertion/deletion polymorphism and congenital urological abnormalities, which result in parenchymal damage in Kuwaiti Arab children.     

779例新生儿眼底筛查结果及新生儿眼底疾病高危因素分析

目的 应用广角数码视网膜成像系统(RetCam3)进行新生儿眼底筛查,了解早产儿及足月小于胎龄儿视网膜疾病的患病率及影响因素.方法 回顾性分析2013年1~12月在我院新生儿病房行RetCam3眼底筛查的早产儿及足月小于胎龄儿的临床病例资料.结果 779例早产儿及足月小于胎龄儿接受筛查,检出有眼底病变患儿100例(12.8%),其中视网膜出血69例(8.9%)、早产儿视网膜病(ROP)10例(1.3%)、眼底渗出9例(1.2%)、视网膜有髓神经纤维4例(0.5%)、视网膜色素沉着3例(0.4%)、先天性白内障和结晶样变性各2例(0.3%)、视网膜母细胞瘤1例(0.1%).Logistic回归分析表明低出生体重、胎龄小和有吸氧史是ROP发病的高危因素(分别OR=0.209、0.248、0.049,均P<0.01);阴道分娩和有机械通气史是导致视网膜出血的高危因素(分别OR=3.196、1.731,均P<0.05).结论 新生儿眼底病变多样且危害严重,早产儿及足月小于胎龄儿应该是眼底筛查的重点人群,临床应加强对高危因素的干预,从而降低ROP和视网膜出血的发生率.     

Norrie Disease: First Mutation Report and Prenatal Diagnosis in an Indian Family

Norrie Disease (ND) is a rare X-linked recessive disorder characterised by congenital blindness due to severe retinal dysgenesis. Hearing loss and intellectual disability is present in 30–50?% cases. ND is caused by mutations in the NDP gene, located at Xp11.3. The authors describe mutation analysis of a proband with ND and subsequently prenatal diagnosis. Sequence analysis of the NDP gene revealed a hemizygous missense mutation arginine to serine in codon 41 (p.Arg41Ser) in the affected child. Mother was carrier for the mutation. In a subsequent di-chorionic di-amniotic pregnancy, the authors performed prenatal diagnosis by mutation analysis on chorionic villi sample at 11?wk of gestation. The fetuses were unaffected. This is a first mutation report and prenatal diagnosis of a familial case of Norrie disease from India. The importance of genetic testing of Norrie disease for confirmation, carrier testing, prenatal diagnosis and genetic counseling is emphasized.     

Mediators involved in retinopathy of prematurity and emerging therapeutic targets

Retinopathy of prematurity (ROP) is a potentially blinding disease of premature infants and despite timely treatment some infants develop retinal detachment and sight loss. Current treatment utilises laser therapy which causes destruction of treated retinal tissue resulting in field loss. There is considerable research work ongoing on neovascular eye disease which is likely to result in antiangiogenic approaches that will arrest the development of ROP by specifically targeting the involved molecular mediators. Some of these new therapeutic interventions have entered clinical trials. This article reviews new information available on the molecular pathogenesis of ROP which may result in novel treatments for ROP; it does not discuss the well-known role of oxygen in the development of ROP.     

Retinopathy of prematurity: the disease process, classifications, screening, treatment, and outcomes

Retinopathy of prematurity (ROP) is the cessation of normal eye development and subsequent abnormal vessel growth that occurs exclusively in premature infants. ROP was first discovered in the 1940s and was for two decades the leading cause of blindness in children. Currently, the disease causes about 500 new cases of blindness per year. The severity of the disease increases with decreasing gestational age. The pathogenesis of ROP involves disruption of normal retinal vascularization. Vessel endothelial growth factor, insulin-like growth factor, and oxygen play important roles in its development. ROP is classified using an international classification system that provides direction for screening and treatment of premature infants. Examinations are performed by ophthalmologists, who identify the scope of vascularization, the degree of abnormal vessel growth, and the amount of the eye that is affected. Treatment modalities include cryosurgery and laser photocoagulation. Long-term outcomes include both structural and functional vision problems.     

急进型后极部早产儿视网膜病的研究进展

急进型后极部早产儿视网膜病（AP-ROP）是一种特殊类型的早产儿视网膜病,其眼底特征表现为视网膜后极部血管扩张迂曲严重,并累及所有象限,而且病情进展非常迅猛。随着越来越多的AP-ROP 病例被发现,并且治疗效果相对差,使AP-ROP 问题日益受到关注。哪些早产儿更易患病？如何做到早期诊断？是否有更好的治疗技术？国内外对此进行了一定的研究探索。该文对AP-ROP 的危险因素、筛查、临床诊断、治疗的临床研究最新进展做一综述。     

早产儿视网膜病发病机制的研究进展

早产儿视网膜病(retinopathy of prematurity,ROP)是一种与早产儿相关的眼部疾病,特点是在视网膜发育过程中血管异常的发生,重症者可引起视网膜脱离而失明,是儿童视力障碍和失明的主要原因.ROP是一个复杂的疾病,除了目前发现的吸氧、胎龄小、低出生体重、细胞因子等因素以外,促红细胞生成素、感染等因素均是可能影响本病发生的因素,根据其发病机制,早期发现、早期治疗已愈发重要,现就ROP发病机制的研究现状及进展进行综述.     

UK population based study of severe retinopathy of prematurity: screening, treatment, and outcome

BACKGROUND: Retinopathy of prematurity (ROP) is one of the few causes of childhood blindness in which severe vision impairment is largely preventable. Ophthalmic screening for ROP is required to identify disease that requires treatment whereby the development of potentially blinding disease can be minimised. OBJECTIVES: To make the first UK population based estimate of the incidence of babies with severe ROP (stage 3 or more); to document their clinical characteristics and management and to evaluate the appropriateness of current ROP screening guidelines in the UK. PATIENTS: Cases were recruited through a national surveillance programme with 1 year ophthalmic follow up and data from clinician completed questionnaires. RESULTS: Between 1 December 1997 and 31 March 1999, 233 preterm babies with stage 3 ROP were identified. Severity (location, extent, and presence of plus disease) was associated with degree of prematurity, most severe in the most premature babies. Fifty nine percent were treated. The UK screening protocol was followed in two thirds of cases, but in the remainder it was begun too late or was too infrequent. Three quarters of the cases were followed up at 1 year, and 13% had a severe vision deficit as a result of ROP. CONCLUSIONS: Visual deficit as a result of ROP in premature babies continues to be a severe disability in some of the survivors of neonatal intensive care. Further efforts are needed to organise treatment regionally to improve outcome and standards of practice.     

Alpha-thalassemia in premature newborns

In this study we have carried out alpha-globin gene mapping, hemoglobin (Hb) Bart's quantitation serum bilirubin, and red blood cell indices determination in a group of Sardinian appropriate for gestational age premature infants (from 32 to 35 wk gestation) in order to define the incidence in this population of the different alpha-thalassemia syndromes, their expression rate, and the correlation between the alpha-globin genotype and phenotype at this developmental stage. The gene frequencies of deletion (-alpha) and nondeletion (alpha alpha th) alpha-thalassemia were 0.29 and 0.04, respectively, and thus not different from those found in full-term newborns from the same population. The majority of premature newborns with a single alpha-globin gene deletion [(-alpha/alpha alpha) genotype] were hematologically silent. Those who manifested increased Hb Bart's (1.2 to 3.4%) had slightly reduced Hb levels (17.4 +/- 2.6 g/dl), mean corpuscular volume (102.6 +/- 6.3 fl), and mean corpuscular Hb (34.8 +/- 2.0 pg) values. Those infants with the deletion of two alpha-globin structural genes (-alpha/-alpha) showed without exception moderate amount of Hb Bart's in the 3.5-8.1% range and an obvious decrease of Hb levels (16.1 +/- 1.6 g/dl) mean corpuscular Hb (30.6 +/- 3.5 pg), and mean corpuscular volume (88.5 +/- 11.5 fl) values. The only infant with the deletion of 3 alpha-globin structural genes had 25% Hb Bart's associated with a moderate microcytic anemia at birth and developed the clinical picture of Hb H disease. Carriers of nondeletion alpha-thalassemia (alpha alpha/alpha alpha th) showed variable amount of Hb Bart's always associated with thalassemia-like red cell indices.(ABSTRACT TRUNCATED AT 250 WORDS)     

Educational paper

Retinopathy of prematurity (ROP) is a proliferative retinal vascular disease affecting the premature infant with an incompletely vascularized retina. The spectrum of ophthalmological findings in ROP exists from minimal sequelae, which do not affect vision, to bilateral retinal detachment and total blindness. With the increased survival of very small infants, retinopathy of prematurity has become one of the leading causes of childhood blindness. Over the past two decades, major advances have been made in understanding the pathogenesis of ROP, to a large extent as a result of changes in clinical risk factors (oxygen and non-oxygen related) and characteristics observed in ROP cases. This article provides a literature review on the evolution in clinical characteristics, classification and treatment modalities and indications of ROP. Special attention is hereby paid to the neonatal factors influencing the development of ROP and to the necessity for everyone caring for premature babies to have a well-defined screening and treatment protocol for ROP. Such screening protocol needs to be based on a unit-specific ROP risk profile and, consequently, may vary between different European regions. Conclusion: Retinopathy of prematurity is an important cause of ocular morbidity and blindness in children. With better understanding of the pathogenesis, screening and treatment guidelines have changed over time and are unit specific.     

肺表面活性蛋白C基因突变相关性新生儿呼吸窘迫综合征2例并文献复习

目的 总结2例肺表面活性蛋白C基因（SFTPC）突变的新生儿呼吸窘迫综合征（NRDS）的临床特点和基因诊断,提高对该病的认识。方法 总结分析本文2例NRDS患儿的临床资料和基因检测结果,并进行文献复习。结果 2例患儿分别为38+3周足月儿和35+2周早产儿,均于生后即发生呼吸窘迫,X线胸片示NRDS,病原学检查均为阴性。均否认肺部疾病家族史。表面活性物质替代治疗和正压辅助通气支持有效。基因检测显示：1例为SFTPC基因c.68G>G/A,p.R23Q杂合错义突变,为首次报道;1例为SFTPC基因c.115G>G/T,p.V39L杂合错义突变,为已报道致病突变。共检索到临床资料完整的SFTPC突变NRDS 6篇文献7例,结合本文2例,9例均生后呼吸窘迫,影像学以弥漫性侵润和间质性改变为主,多予机械通气、PS对症支持治疗,2例死亡,1例间质性肺病,1例支气管肺发育不良,4例随访健康,1例失访。结论 中国NRDS病例中存在SFTPC基因突变,相关基因突变的识别,可为早期干预、预后判断以及遗传咨询提供依据。     

肺表面活性物质蛋白 B、C 基因变异与蒙古族早产儿 呼吸窘迫综合征相关性研究

目的研究肺表面活性物质蛋白(SP)B、SP-C基因外显子4(exon4)区域基因变异与蒙古族早产儿呼吸窘迫综合征(RDS)的相关性。方法选择住院治疗的无血缘关系的蒙古族RDS早产儿50例(男31例,女19例),同期、同民族和同群体中无血缘关系的非RDS早产儿50例为对照组(男27例,女23例),分别用聚合酶链式反应(PCR)基因多态性分析和基因检测技术对SP-B、SP-C基因exon4区域基因进行测序,并比较两组患儿SP-B基因exon4区域1580位点基因变异及基因型频率、SP-C基因exon4区域c.571C A(T138N)位点基因变异及基因型频率的差异。结果检测出SP-B基因exon4区域1580位点基因变异,RDS组14例,变异率为28%,非RDS组11例,变异率为22%,两组差异无统计学意义(χ2=0.480,P 0.05)。RDS组1580位点CC、TT、CT基因型频率分别为16%、72%和12%,非RDS组则分别为10%、78%和12%;RDS组C等位基因频率为22%、T等位基因频率为78%,非RDS组则分别为16%、84%;两组间基因型频率差异无统计学意义(χ~2=1.170,P 0.05)。检测出SP-C基因exon 4区域c.571 C A(T 138 N)位点基因变异,RDS组41例,变异率为82%,非RDS组6例,变异率为12%,两组间差异有统计学意义(χ~2 =49.177,P 0.05)。RDS组c.571C A(T138N)位点CC、AA、AC三种基因型频率分别为18%、50%和32%,非RDS组分别为88%、8%和4%;RDS组C等位基因频率为34%、A等位基因频率为66%,非RDS组则分别为90%、10%,两组间A等位基因型频率的差异有统计学意义(χ~2=66.553,P 0.05)。结论携带SP-C基因exon 4区域c.571 C A(T 138 N)位点A等位基因的蒙古族早产儿患RDS的风险更高,而SP-B基因exon 4区域1580位点基因变异与蒙古族早产儿发生RDS无关。