Familial insertion (3;5)(q25.3;q22.1q31.3) with deletion or duplication of chromosome region 5q22.1-5q31.3 in ten unbalanced carriers

We report on the clinical and cytogenetic data of a large family with an unbalanced insertion translocation (3;5)(q25.3;q22.1q31.3). Analysis of GTG-banded chromosomes demonstrated that unbalanced inheritance of a parental insertion translocation caused either a partial deletion or duplication 5q in this family. The derivative chromosomes were characterized further using microdissection and FISH with band-specific probes. The clinical picture of the proband with a partial deletion of chromosome 5 was characterized by moderate psychomotor retardation, mild facial dysmorphism, cleft palate, and single transverse crease. The family members with a partial duplication of chromosome 5 were borderline intelligent, had mild facial dysmorphism, a cardiac anomaly, and a high-pitched voice. The unbalanced carriers were compared with patients reported in the literature with a duplication or deletion of chromosome region 5q22.1 --> 5q31.3.     

Segregation of a familial balanced (12;10) insertion resulting in dup(10)(q21.2q22.1) and del(10)(q21.2q22.1) in first cousins

An interchromosomal insertion in 3 generations of a family was ascertained through two developmentally delayed first cousins. Cytogenetic analysis using G-banding and chromosome painting showed an apparently balanced direct insertion of chromosome 10 material into chromosome 12, ins(12;10)(q15;q21.2q22.1), in the mothers and grandfather of these children. The proposita inherited only the derivative 10 chromosome, resulting in deletion of 10q21.2 → 22.1 while her cousin inherited only the derivative 12, resulting in duplication of 10q21.2 → 22.1. A comparison of the proposita with published deletion cases suggests a pattern of anomalies attributable to deletion of the 10q21 → q22 region: developmental delay, hypotonia, a heart murmur, telecanthus, broad nasal root and ear abnormalities. This is the first report of a nontandem duplication of the 10q21 → q22 region. The phenotype of the cousin with the duplication does not overlap greatly with published tandem 10q duplications. Finally, this report reaffirms the importance of obtaining family studies of patients with interstitial chromosomal abnormalities. Am J. Med. Genet. 69:188–193, 1997. © 1997 Wiley-Liss, Inc.     

原发性开角型青光眼患者Myocilin基因的单核苷酸多态性

目的　探讨 Myocilin(MYOC)基因的单核苷酸多态性 (single nucleotide polymorphisms,SNPs)及其与原发性开角型青光眼 (primary open- angle glaucoma,POAG)发病的关系。方法　应用高通量构象敏感性凝胶电泳和荧光标记自动测序法筛选和鉴定香港 15 7例 POAG散发患者和 15 5名对照 MYOC基因的 SNPs。结果　在 MYOC基因所有 3个外显子及邻近的非编码区共检出 17种 SNPs:1- 83G→ A、G12 R、P16 L、A17S、R4 6 X、R76 K、R91X、T12 3T、D2 0 8E、L 2 15 P、730 35 A→ G、A2 6 0 A、I2 88I、E30 0 K、T35 3I、Y4 71C和 15 15 73G→ C。其中 ,R91X、E30 0 K和 Y4 71C仅在 POAG患者中检测到。此外 ,15 15 73G→ C各基因型在 POAG患者与对照人群中的分布差异具有显著意义 ,POAG患者中 CG型频率为 0 .6 % ,低于对照组的 4 .5 % (P=0 .0 36 )。其余 16种 SNPs各基因型在两组人群中的分布差异均无显著意义。结论　 MYOC基因多态性可能与中国人 POAG发病有关 ,提示 MYOC基因是 POAG的相关基因。     

一原发性开角型青光眼家系OPTN基因4号和14号外显子基因突变研究

目的 研究中国大陆地区一原发性开角型青光眼(POAG)家系OPTN基因4号和14号外显子的突变情况.方法 采用聚合酶链反应(PCR)扩增POAG家系39例成员的OVTN基因4号和14号外显子,并对PCR产物进行单链构象多态性(SSCP)分析,对14号外显子同时利用内切酶Pag Ⅰ进行限制件片段长度多态性(RFLP)分析.同时用100例与该家系无亲缘关系的健康体检者进行对照试验.结果 该POAG家系成员OPTN基因4号和14号外显子通过SSCP分析均未发现突变,酶切14号外显子发现有2例可疑情况.正常对照组中SSCP分析和酶切分析均未发现突变及其可疑情况.结论 该家系开角型青光眼的发病可能并非由于OPTN基因4号和14号外显子的基因突变引起,寻找致病原因仍需作进一步研究.同时,SSCP分析和酶切方法的联合应用,可以提高检测的敏感性.     

Analysis of myocilin gene mutations in Japanese patients with normal tension glaucoma and primary open-angle glaucoma

The myocilin gene was identified as a gene (MYOC) that caused primary open-angle glaucoma (POAG). Although a normal tension glaucoma (NTG) patient with the myocilin gene mutation was previously reported, no study using large numbers of patients with NTG has been reported. Single-strand conformation polymorphism analysis and subsequent sequence analysis were performed for genotyping the myocilin gene in 114 unrelated Japanese patients with NTG. One hundred and nineteen patients with POAG and 100 control subjects without glaucoma were studied as reference subjects. Five amino acid sequence changes of the myocilin were identified: Arg46Stop (one NTG), Arg76Lys (four NTG, 10 POAG, seven control), Arg158Gln (one NTG, one POAG, one control) found in only Japanese, Asp208Glu (four NTG, three POAG, one control), Pro481Ser (one control). Pro481Ser was novel. Arg76Lys always occurred with 1-83 from G to A in the promoter as it was reported in Chinese. Although some Japanese patients with NTG had sequence changes of the myocilin gene, there were no apparent specific mutations in patients with NTG.     

Identification of a new GLC1A mutation in a sporadic,primary open-angle glaucoma in Japan

Glaucoma is a major cause of blindness characterized by progressive degeneration of the optic nerve and elevated intraocular pressure. Recent studies have revealed a genetic basis for a substantial proportion of cases of familial primary open-angle glaucoma (POAG) and the gene causing the abnormality has been identified. Sequence variations that meet the criteria for a probable disease-causing mutation have been found in the American and European populations. In this study, we examined 58 cases of sporadic glaucoma from Japan to clarify the relationship between the mutations of the GLC1A gene and sporadic glaucoma in Japan. We have examined 33 POAG, 17 primary closed-angle glaucomas, 6 normal-tension glaucomas and 2 steroid-induced glaucomas for mutation of the GLC1A gene using polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis and direct DNA sequencing studies. We identified a previously unreported GGT right curved arrow GAT transition at codon 451 in exon 3, resulting in a glycine to asparagine substitution in one POAG patient. No other mutations of the GLC1A gene were found in other types of glaucoma. These findings further emphasize the importance of GLC1A mutation in the development of POAG.     

Mutations in the optineurin gene in Japanese patients with primary open-angle glaucoma and normal tension glaucoma

The optineurin gene (OPTN) was identified as a gene that causes primary open-angle glaucoma (POAG) and normal tension glaucoma (NTG). To investigate the frequency of sequence changes in OPTN in Japanese glaucoma patients, single-strand conformation polymorphism analysis and subsequent sequence analysis were performed for genotyping OPTN in 165 unrelated Japanese patients with POAG and 148 patients with NTG, with 196 control subjects without glaucoma as reference subjects. Out of four mutations reported to be associated with risk and to cause disease in Caucasian patients, sequence alterations in 458G > A and 691_692insAG were not detected in any investigated Japanese patients with glaucoma, and alterations in 1944G > A and 603T > A, were present in similar frequencies in glaucoma patients and control subjects. The current results suggest that there may be certain racial differences between Japanese and Caucasians with respect to OPTN genotypes.     

Familial short stature due to a 5q22.1-q23.2 duplication refines the 5q duplication spectrum

We identified a maternally inherited 14.2Mb duplication 5q22.1-q23.2 in two female siblings and their mother by molecular karyotyping. Both siblings were small for gestational age and presented with pronounced postnatal growth retardation, mild motor delay, congenital heart disease in one of the siblings, and distinct facial dysmorphism. As this duplication is one of the smallest reported 5q duplications, short stature and facial dysmorphism can be attributed to duplications of 5q22, whereas severe mental retardation is not part of the phenotypic spectrum of the 5q22.1-q23.2 region. Congenital heart defects, as observed in other 5q duplications, have a variable penetrance. We compared the facial features of patients with 5q duplications and found some consistent features such as high arched eyebrows, bulbous nasal tip and small lips with thin vermilion border.     

Del(14)(q22.1q23.2) in a patient with anophthalmia and pituitary hypoplasia

Only few cases with an interstitial deletion of chromosome 14 have been described so far. We report on a 21-month-old girl with an interstitial deletion of the long arm of chromosome 14, del(14)(q22.1q23.2). She presented with bilateral anophthalmia, absent left external auditory canal, facial asymmetry, microretrognathia, hypotonia, and psychomotor retardation. Skeletal X-rays showed lambdoid craniosynostosis, a very small sella turcica and cervical vertebral anomalies. Brain MRI showed the absence of the optic chiasm, an hypoplastic pituitary gland, and cortical atrophy. No cardiac or abdominal malformations were found. Two other patients with a similar deletion, (del(14)(q22.1q23) and del(14)(q22.1q22.3)), are described. Both presented with bilateral anophthalmia and absent pituitary or hypogonadism. These three cases suggest that the region 14q22 is important for eye and pituitary development. Interestingly, the human BMP-4 gene, a member of the TGF-β superfamily, maps to 14q22-q23 and may play a role in pituitary and eye development. Am. J. Med. Genet. 77:162–165, 1998. © 1998 Wiley-Liss, Inc.     

BDNF and HSP gene polymorphisms and their influence on the progression of primary open-angle glaucoma in a Polish population

Introduction

Glaucoma is a neurodegenerative disease that is often associated with high intraocular pressure (IOP). One of the effects of elevated IOP is disorder of neurotrophic molecules transport, including brain-derived neurotrophic factor (BDNF) and recruit specific cellular proteins called “heat shock proteins” (HSPs). The aim of this study was to evaluate a relationship between the BDNF and HSP70-1 gene polymorphisms with risk occurrence of primary open-angle glaucoma (POAG).

Material and methods

The study consisted of 167 patients with POAG (mean age: 73 ±9) and 193 healthy subjects (mean age: 64 ±13). Genomic DNA was extracted from peripheral blood. Analysis of the gene polymorphisms was performed using PCR-RFLP, using the following restriction enzymes: NlaIII (rs6265) and BsrBI (rs1043618). The Heidelberg retinal tomography (HRT) clinical parameters were also analyzed. The odds ratios (ORs) and 95% confidence intervals (CIs) for each genotype and allele were calculated.

Results

Comparison of the distributions of genotypes and alleles of the 196G/A polymorphism of the BDNF gene as well as 190G/C polymorphism of the HSP70-1 gene and analysis of the odds ratio (OR) showed no statistically significant differences between POAG patients and controls (p > 0.05). However, there was a statistically significant association of the 196G/A of BDNF and 190G/C of HSP70-1 gene polymorphisms with progression of POAG depending on values of clinical parameters. 196G/A of BDNF correlated with the parameters GDx and RA (p = 0.03; p = 0.002, respectively), while 190G/C of HSP70-1 correlated with c/d and RA (p = 0.014, p = 0.024, respectively).

Conclusions

The BDNF 196G/A and HSP70-1 190G/C gene polymorphisms may be related to progression of POAG.     

Race, ethnicity and prevalence of primary open-angle glaucoma

BACKGROUND: Recently, some authors pooled data from studies on the Dutch, Australians and Americans of European origin in an attempt to predict the prevalence of primary open-angle glaucoma (POAG) in the United States. PURPOSE: To examine potential ethnic diversity in the prevalence of POAG among populations of the "same race." Methods: Medical literature was searched, and 11 population-based studies on populations of African origin and five on populations of European origin were identified. RESULTS: The prevalence of POAG was significantly higher in white Australians than in the Dutch (p<0.001) and was significantly lower (p<0.001) among black populations in South Africa, Nigeria, Tanzania and the United States than in Ghana, St. Lucia or Barbados. Notably, the prevalence was significantly lower in Afro Caribbeans living in London than in St. Lucia or Barbados (p<0.001). There was, however, inconsistency in the definition of POAG among the different studies. CONCLUSIONS: There is a wide range in the prevalence of POAG among populations of the same "race," which might be attributed to the different methodology and definition of POAG; potential difference in social, behavioral and environmental factors; and/or genetic predisposition. Scrutiny is warranted when pooling data from different ethnic groups of the "same race" in meta-analyses.     

De novo dup(X)(q22.1q25) in a girl with an abnormal phenotype

Duplication of a portion of Xq has been observed in males with abnormalities. In some cases, their mothers or even grandmothers had the same duplication but did not show any phenotypic abnormalities. However, a few cases of females with a de novo Xq duplication do present some abnormalities. We describe a 16-month-old girl with short stature, motor delay with hypotonia, scoliosis, right hemiatrophy, and ptosis of the right eye, with an Xq duplication. The duplicated region is read dir dup(X)(q22.1q25).     

Re-evaluation of GM2346 from a del(16)(q22) to t(4;16)(q35;q22.1)

Reassessment of the cytogenetics of a patient previously karyotyped as del(16)(q22) demonstrates the presence of a balanced translocation, t(4;16)(q35;q22.1). This patient should not be included in any future comparison involving the clinical features of patients with deletions of the long arm of chromosome 16.     

t(1;18)(q32.1;q22.1) associated with genitourinary malformations

We report a male infant who has impaired penile development, hypospadias, and mild developmental delay with a 46,XY,t(1;18)(q32.1;q22.1) karyotype. Fluorescent in situ hybridization (FISH) was performed to more precisely map the translocation breakpoint. The translocation breakpoint maps to a region that has been implicated in genitourinary malformations in the 18q- syndrome. This case report suggests that a gene involved in genitourinary development maps at or near the chromosome 18 translocation breakpoint.     

A de novo interstitial deletion of 15(q21.2q22.1) in a moderately retarded adult male.

An adult male is described with a de novo deletion 15q21.2-q22.1. He shares some minor dysmorphic features with similar cases but the degree of mental retardation is markedly less severe.     

A new interstitial deletion of 4q (q21.1::q22.1).

A unique case of de novo interstitial deletion of chromosome 4 is described involving loss of band q21. The male newborn had multiple abnormalities including frontal bossing, prominent occiput, low set ears, micrognathia, short sternum, short, broad hands and feet, agenesis of the corpus callosum, and cardiac defects. The phenotypic abnormalities are compared with other reported cases of deletion 4q involving adjacent regions.