Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Recessive”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 595 records · Page 33Linked to original sources
PubMed2005

Interest in periodontology and preferences for treatment of localized gingival recessions.

OBJECTIVES: The purpose of this study was to evaluate the views, knowledge and preferences of a large sample of practising dentists in periodontics, focusing specifically on the treatment of gingival recessions, and to compare the findings with the current evidence available in the dental literature. METHODS: We conducted a cross-sectional postal survey of 3780 dentists, representing the majority of all dentists working in Switzerland. The questionnaire consisted of 17 questions, most of them giving the possibility of multiple choices of answers. The demographic profile, interests and satisfaction in periodontics were associated with the choice of treatment options offered for the management of six clinical situations. RESULTS: One thousand two hundred and one dentists sent back the questionnaire within three months and were thus included in the analysis. In general, the interest and the satisfaction in periodontics were moderate to high (6-7 on an analogue scale from 1 to 10). Specialists in periodontics indicated a significantly higher interest and satisfaction in periodontics than the general dentists (p<0.001), and practitioners working in urban areas indicated a slightly higher interest (p=0.027) and satisfaction (0.047) than their colleagues established in a rural setting. The predominant indication of root coverage procedures was aesthetics (90.7%). The region in which dentists worked was the only significant predictor for choosing "no treatment" of buccal recessions: dentists from the German-speaking part were significantly less inclined to surgically treat gingival recessions than their colleagues from the French or Italian part. For those who opted for therapy, a free tissue graft was generally the favourite option, followed by a connective tissue graft and a coronally advanced flap. Throughout, only a small fraction of the dentists considered using a guided tissue regeneration procedure. The relative odds for not extracting teeth with severe periodontal disease were higher if the dentist was a specialist than a generalist. Satisfaction in practicing periodontics also positively strengthened the inclination towards keeping severely compromised teeth. CONCLUSIONS: Aesthetic concerns were the predominant indication for root coverage procedures. Further research should therefore include aesthetic aspects as primary clinical outcome variables. Specific training of dentists and their satisfaction in periodontics influenced treatment decisions. Specialists involved in continuing education should inform practicing dentists more efficiently on the potential and usefulness of periodontal therapy for saving and maintaining periodontally compromised teeth.

Adult↗
PubMed1999

A recurrent frameshift mutation in exon 19 of the type VII collagen gene (COL7A1) in Mexican patients with recessive dystrophic epidermolysis bullosa.

Dystrophic epidermolysis bullosa (DEB) is an inherited blistering skin disorder caused by mutations in the type VII collagen gene (COL7A1). In this study, we determined the molecular basis of autosomal recessive DEB in a 19-year-old Hispanic Mexican woman by PCR amplification of genomic DNA, heteroduplex analysis, and automated sequencing of heteroduplex bandshifts. This approach revealed a homozygous frameshift mutation, 2470insG, in exon 19 of COL7A1 and resulted in attenuated basement membrane zone expression of type VII collagen, a reduced number of anchoring fibrils at the dermal-epidermal junction, and a sub-lamina densa level of blister formation. Clinically, the patient had widespread trauma-induced skin fragility and complete loss of the nails, but had less pseudosyndactyly of the fingers and toes and milder mucosal involvement compared to most patients with the generalized form of this genodermatosis. We also screened 7 other Hispanic-Mexican patients with recessive DEB, none of whom were known to be related to this individual, for the mutation 2470insG using heteroduplex analysis and direct sequencing and detected this mutation on 7/14 alleles. Haplotype analysis using intragenic COL7A1 and flanking polymorphisms and microsatellite markers revealed that all the mutant alleles had arisen on similar allelic backgrounds, consistent with propagation of a common Hispanic Mexican ancestral haplotype. In view of the high allelic frequency of the mutation 2470insG in the patients studied, we recommend initial screening for this mutation when attempting to identify the molecular pathology of recessive DEB in Hispanic Mexican patients.

Adult↗
PubMed1999

Diagnostic dilemma of "sporadic" cases of dystrophic epidermolysis bullosa: a new dominant or mitis recessive mutation?

Dystrophic forms of epidermolysis bullosa (DEB), characterized by mutations in the type VII collagen gene (COL7A1), are inherited either in an autosomal dominant or autosomal recessive fashion, and sporadic, de novo cases have also been reported. Clinically, the dominant forms (DDEB) can be indistinguishable from the mild, mitis forms of recessively inherited DEB (M-RDEB). This situation poses a dilemma in case of families with 1 mildly affected individual and clinically normal parents: Is it a new dominant or mitis recessive DEB? In this study we review 2 cases with mild DEB, the parents being clinically normal. One of the cases was shown to be a compound heterozygote for 2 silent missense mutations (R2063W/G2366S), thus being diagnosed as M-RDEB. The second case had a single glycine substitution mutation (G2079E) in COL7A1 and had therefore DDEB. These findings have implications for the genetic counseling of these families concerning the risk of recurrence of the disease in subsequent pregnancies in the present and future generations.

Amino Acid Substitution↗
PubMed2005

New surgical approach for root coverage of localized gingival recession with acellular dermal matrix: a 12-month comparative clinical study.

BACKGROUND: Acellular dermal matrix graft (ADMG) has been used as an advantageous substitute for autogenous subepithelial connective tissue graft (SCTG). However, the surgical techniques used were primarily developed for the SCTG, and they may not be adequate for ADMG since it has a different healing process than SCTG owing to its different vascular and cellular structures. This study compared the 1-year clinical outcome of a new surgical approach with the outcome of a conventional procedure for the treatment of localized gingival recessions, both performed using the ADMG. MATERIALS AND METHODS: The clinical parameters-probing depth, relative clinical attachment level, gingival recession (GR), and width of keratinized tissue-of 32 bilateral Miller Class I or II gingival recessions were assessed at baseline and 12 months postoperatively. RESULTS: Significant clinical changes for both surgical techniques were achieved after this period, including GR reduction from 3.4 mm presurgery to 1.2 mm at 1 year for the conventional technique and from 3.9 mm presurgery to 0.7 mm at 1 year for the new technique. The percentage of root coverage was 62.3% and 82.5% for the conventional and new techniques, respectively. Comparisons between the groups after this period by Mann-Whitney rank sum test revealed statistically significant greater reduction of GR favoring the new procedure (p = .000). CLINICAL SIGNIFICANCE: Based on the results of this study, it can be concluded that a new surgical technique using an ADMG is more suitable for root coverage when compared with the conventional technique. The results revealed a statistically significant improvement in clinical performance with the ADMG approach.

Adult↗
PubMed1987

Homozygosity mapping: a way to map human recessive traits with the DNA of inbred children.

An efficient strategy for mapping human genes that cause recessive traits has been devised that uses mapped restriction fragment length polymorphisms (RFLPs) and the DNA of affected children from consanguineous marriages. The method involves detection of the disease locus by virtue of the fact that the adjacent region will preferentially be homozygous by descent in such inbred children. A single affected child of a first-cousin marriage is shown to contain the same total information about linkage as a nuclear family with three affected children. Calculations show that it should be practical to map a recessive disease gene by studying DNA from fewer than a dozen unrelated, affected inbred children, given a complete RFLP linkage map. The method should make it possible to map many recessive diseases for which it is impractical or impossible to collect adequate numbers of families with multiple affected offspring.

Chromosome Mapping↗
PubMed1996

Isolation, purification, and in vitro characterization of recessive-lethal-mutant RNA polymerases from Escherichia coli.

The beta subunit of prokaryotic RNA polymerase shares significant sequence similarity with its eukaryotic and archaeal counterparts across most of the protein. Nine segments of particularly high similarity have been identified and are termed segments A through I. We have isolated severely defective Escherichia coli RNA polymerase mutants, most of which are unable to support bacterial growth. The majority of the substitutions affect residues in one of the conserved segments of beta, including invariant residues in segments D (amino acids 548 to 577), E (amino acids 660 to 678), and I (amino acids 1198 to 1296). In addition, recessive-lethal mutations that affect residues highly conserved only among prokaryotes were identified. They include a substitution in the extreme amino terminus of beta, a region in which no substitutions have previously been identified, and one rpoB mutation that truncates the polypeptide without abolishing minimal polymerase function in vitro. To examine the recessive-lethal alleles in vitro, we devised a novel method to remove nonmutant enzyme from RNA polymerase preparations by affinity tagging the chromosomal rpoB gene. In vitro examination of a subset of purified recessive-lethal RNA polymerases revealed that several substitutions, including all of those altering conserved residues in segment I, severely decrease transcript elongation and increase termination. We discuss the insights these mutants lend to a structure-function analysis of RNA polymerase.

Amino Acid Sequence↗
PubMed2006

Autosomal recessive corneal endothelial dystrophy (CHED2) is associated with mutations in SLC4A11.

OBJECTIVE: To map and identify the gene for autosomal recessive congenital hereditary endothelial dystrophy (CHED2, OMIM 217700), a disorder characterised by diffuse bilateral corneal clouding that may lead to visual impairment and requiring corneal transplantation. METHODS: Members of 16 families with autosomal recessive CHED were genotyped for 13 microsatellite markers at the CHED2 locus on chromosome 20p13-12. Two-point linkage analysis was carried out using the FASTLINK version of the MLINK program. Mutation screening was carried out by amplification of exons and flanking regions by polymerase chain reaction, followed by direct automated sequencing. RESULTS: Linkage and haplotype analysis placed the disease locus within a 2.2 cM (1.3 Mb) interval flanked by D20S198 and D20S889, including SLC4A11. The maximum LOD score of 11.1 was obtained with D20S117 at theta = 0. Sequencing of SLC4A11 showed homozygotic mutations in affected members from 12 of 16 families. CONCLUSION: These results confirm that mutations in the SLC4A11 gene cause autosomal recessive CHED.

Anion Transport Proteins↗
PubMed1994

Autosomal recessive disorders among Arabs: an overview from Kuwait.

Kuwait has a cosmopolitan population of 1.7 million, mostly Arabs. This population is a mosaic of large and small minorities representing most Arab communities. In general, Kuwait's population is characterized by a rapid rate of growth, large family size, high rates of consanguineous marriages within the Arab communities with low frequency of intermarriage between them, and the presence of genetic isolates and semi-isolates in some extended families and Bedouin tribes. Genetic services have been available in Kuwait for over a decade. During this time it has become clear that Arabs have a high frequency of genetic disorders, and in particular autosomal recessive traits. Their pattern is unique and some disorders are relatively common. Examples are Bardet-Biedl and Meckel syndromes, phenylketonuria, and familial Mediterranean fever. A relatively large number of new syndromes and variants have been delineated in Kuwait's population, many being the result of homozygosity for autosomal recessive genes that occurred because of inbreeding. Some of these syndromes have subsequently been found in other parts of the world, negating the concept of the private syndrome. This paper provides an overview of autosomal recessive disorders among the Arabs in Kuwait from a personal perspective and published studies, and highlights the need for genetic services in Arab countries with the goal of prevention and treatment of genetic disorders.

Chromosome Aberrations↗
PubMed1995

Use of type VII collagen gene (COL7A1) markers in prenatal diagnosis of recessive dystrophic epidermolysis bullosa.

Generalised recessive dystrophic epidermolysis bullosa (EB) is a severe inherited disease in which patients suffer from blistering and scarring of the skin and mucous membranes after minor mechanical trauma. Tight genetic linkage has been established to the type VII collagen gene (COL7A1) at 3p21, with no evidence of locus heterogeneity. Several COL7A1 mutations have now been identified in recessive dystrophic EB patients. Prenatal diagnosis has been performed by examination of a fetal skin biopsy taken at about 16 weeks' gestation, and relies on identification of characteristic ultrastructural and immunohistochemical changes. We have now achieved a first trimester prenatal diagnosis using intragenic and flanking COL7A1 markers in a pregnancy at risk for recessive dystrophic EB. Segregation of the informative markers predicted the baby would be an unaffected carrier. The pregnancy continued to term and a healthy baby was born, confirming this result.

Collagen↗
PubMed1980

Autosomal recessive forms of hereditary motor and sensory neuropathy.

Six families are described with hereditary motor and sensory neuropathy (HMSN) of probable autosomal recessive inheritance. Four of these were classified as HMSN type I and two as type II. The consanguinity rate in this series was high, suggesting that these recessive genes are rare. In comparison with the dominantly inherited forms of these disorders, the mean age of onset was significantly earlier for the type II cases but did not differ for the type I patients. Motor nerve conduction velocity was significantly less for the type I cases but did not differ for the type II form. The recessive type I cases tended to show a greater incidence of weakness, ataxia, tendon areflexia and scoliosis than in the dominant form. The importance of differentiating such cases from Friedreich's ataxia is emphasised.

Adolescent↗
PubMed1976

Dominant-and-recessive epistasis in a homeotic mosquito mutant.

Following selection for 15 generations a pure strain of a homeotic mutant spur was isolated from a Brazilian population of the mosquito Culex pipiens fatigans. Monohybrid crosses showed a 13:3 segregation indicating dominant-and-recessive epistasis for wild-type vs. spur. This implies that a dominant allele at one locus and a recessive at the other interact to produce the mutant phenotype. Dihybrid crosses with linkage group II markers yellow and ruby gave 39:13:9:3 ratios indicating independent segregation. However, the dihybrid cross with linkage group I marker maroon showed a highly significant departure from 39:13:9:3 ratio. Data available indicate that the phenotype spur is controlled by a dominant epistat in linkage group III and a recessive epistat (approximately 31.9 crossover units from maroon) in linkage group I.

Alleles↗
PubMed1998

Progression of visual field loss in patients with retinitis pigmentosa of sporadic and autosomal recessive types.

PURPOSE: We examined the natural course of patients with retinitis pigmentosa of the eight sporadic and five autosomal recessive forms over 5 years. METHODS: We measured the areas of the visual fields by Goldmann perimetry using a digitizer and a computer software. RESULTS: The visual field of V-4 isopters in 4 sporadic cases was approximately 200 cm2 during 30 years after the initial examination, but decreased down to 40 cm2 in the next 10 years. The visual field was reduced to half the normal field in 3 autosomal recessive cases early below the age of 25 years. In 4 sporadic and 2 autosomal recessive cases, the inferior temporal visual field was the widest at the onset of the disease, but exhibited the most severe loss. The superior nasal area was the narrowest initially, and showed the mildest progression. CONCLUSIONS: The visual field in retinitis pigmentosa is constricted age-dependently with severe loss of the inferior temporal visual area and mild damage to the superior nasal area.

Adolescent↗
PubMed1999

Characterization of a new form of inherited hypercholesterolemia: familial recessive hypercholesterolemia.

We previously described a Sardinian family in which the probands had a severe form of hypercholesterolemia, suggestive of familial hypercholesterolemia (FH). However, low density lipoprotein (LDL) receptor activity in fibroblasts from these subjects and LDL binding ability were normal. The characteristics of the pedigree were consistent with an autosomal recessive trait. Sitosterolemia and pseudohomozygous hyperlipidemia were ruled out. A second Sardinian kindred with similar characteristics was identified. Probands showed severe hypercholesterolemia, whereas their parents and grandparents were normolipidemic. FH, familial defective apoprotein (apo) B, sitosterolemia, and cholesteryl ester storage disease were excluded by in vitro studies. We addressed the metabolic basis of this inherited disorder by studying the in vivo metabolism of LDL in 3 probands from these 2 families. 125I-LDL turnover studies disclosed a marked reduction in the fractional catabolic rate (0.19+/-0.01 versus 0.36+/-0.03 pools per day, respectively; P<0.001) and a significant increase in the production rate [20.7+/-4.4 versus 14. 0+/-2.4 mg. kg-1. d-1, respectively; P<0.01] of LDL apoB in the probands compared with normolipidemic controls. We then studied the in vivo biodistribution and tissue uptake of 99mtechnetium-labeled LDL in the probands and compared them with those in normal controls and 1 FH homozygote. The probands showed a significant reduction in hepatic LDL uptake, similar to that observed in the FH homozygote. A reduced uptake of LDL by the kidney and spleen was also observed in all patients. Our findings suggest that this recessive form of hypercholesterolemia is due to a marked reduction of in vivo LDL catabolism. This appears to be caused by a selective reduction in hepatic LDL uptake. We propose that in this new lipid disorder, a recessive defect causes a selective impairment of LDL receptor function in the liver.

Adult↗
PubMed2002

Myosin light chain mutation causes autosomal recessive cardiomyopathy with mid-cavitary hypertrophy and restrictive physiology.

BACKGROUND: Autosomal dominant hypertrophic cardiomyopathy (HCM) is caused by inherited defects of sarcomeric proteins. We tested the hypothesis that homozygosity for a sarcomeric protein defect can cause recessive HCM. METHODS AND RESULTS: We studied a family with early-onset cardiomyopathy in 3 siblings, characterized by mid-cavitary hypertrophy and restrictive physiology. Genotyping of DNA markers spanning 8 genes for autosomal dominant HCM revealed inheritance of an identical paternal and maternal haplotype at the essential light chain of myosin locus by the affected children. Sequencing showed that these individuals were homozygous for a Glu143Lys substitution of a highly conserved amino acid that was absent in 150 controls. Family members with one Glu143Lys allele had normal echocardiograms and ECGs, even in late adulthood, whereas those with two mutant alleles developed severe cardiomyopathy in childhood. These findings, coupled with previous studies of myosin light chain structure and function in the heart, suggest a loss-of-function disease mechanism. CONCLUSIONS: Distinct mutations affecting the same sarcomeric protein can cause either dominant or recessive cardiomyopathy. Electrostatic charge reversal of a highly conserved amino acid may be benign in the heterozygous state as the result of compensatory mechanisms that preserve cardiac structure and function. By contrast, homozygous carriers of a sarcomeric protein defect may have a malignant course. Recognizing recessive inheritance in children with cardiomyopathy is essential for appropriate family counseling.

Adolescent↗
PubMed2004

A homozygous splice mutation in the HSF4 gene is associated with an autosomal recessive congenital cataract.

PURPOSE: To map the locus and identify the gene causing autosomal recessive congenital cataracts in a large consanguineous Tunisian family. METHODS: DNA was extracted from blood samples from a large Tunisian family with an autosomal recessive, congenital, total white cataract. A genome-wide scan was performed with microsatellite markers. All exons and the splice sites of the HSF4 gene were sequenced in all members of the Tunisian family and in control individuals. RT-PCR was used to detect different transcripts of the HSF4 gene in the human lens. The transcripts were cloned in a TA cloning vector and sequenced. RESULTS: Two-point linkage analyses showed linkage to markers on 16q22 with a maximum lod score of 17.78 at theta = 0.01 with D16S3043. Haplotype analysis refined the critical region to a 1.8-cM (4.8-Mb) interval, flanked by D16S3031 and D16S3095. This region contains HSF4, some mutations of which cause the autosomal dominant Marner cataract. Sequencing of HSF4 showed a homozygous mutation in the 5' splice site of intron 12 (c.1327+4A-->G), which causes the skipping of exon 12. A more detailed study of the transcripts resulting from alternative splicing of the HSF4 gene in the lens is also reported, showing the major transcript HSF4b. CONCLUSIONS: This is the first report describing association of an autosomal recessive cataract with the HSF4 locus on 16q21-q22.1 and the first description of HSF4 splice variants in the lens showing that HSF4b is the major transcript.

Cataract↗
PubMed2005

A new locus for autosomal recessive nuclear cataract mapped to chromosome 19q13 in a Pakistani family.

PURPOSE: To identify the disease locus of autosomal recessive congenital nuclear cataracts in a consanguineous Pakistani family. METHODS: A large Pakistani family with multiple individuals affected by autosomal recessive congenital cataracts was ascertained. Patients were examined, blood samples were collected, and DNA was isolated. A genome-wide scan was performed using 382 polymorphic microsatellite markers on genomic DNA from affected and unaffected family members. Two-point lod scores were calculated, and haplotypes were formed by inspection. RESULTS: In the genome-wide scan, a maximum lod score of 2.89 was obtained for marker D19S414 on 19q13. Fine mapping using D19S931, D19S433, D19S928, D19S225, D19S416, D19S213, D19S425, and D19S220 markers from the Généthon database showed that markers in a 14.3-cM (12.66-Mb) interval flanked by D19S928 and D19S420 cosegregated with the cataract locus. Lack of homozygosity further suggests that the cataract locus may lie in a 7-cM (4.3-Mb) interval flanked by D19S928 proximally and D19S425 distally. On fine mapping, a maximum lod score of 3.09 was obtained with D19S416 at theta = 0. CONCLUSIONS: Linkage analysis identified a new locus for autosomal recessive congenital nuclear cataracts on chromosome 19q13 in a consanguineous Pakistani family.

Cataract↗
PubMed2005

Autosomal recessive retinitis pigmentosa is associated with mutations in RP1 in three consanguineous Pakistani families.

PURPOSE: To localize and identify the gene and mutations causing autosomal recessive retinitis pigmentosa in three consanguineous Pakistani families. METHODS: Blood samples were collected and DNA was extracted. A genome-wide scan was performed by using 382 polymorphic microsatellite markers on genomic DNA from affected and unaffected family members, and lod scores were calculated. RESULTS: A genome-wide scan of 25 families gave an hlod = 4.53 with D8S260. Retinitis pigmentosa in all three families mapped to a 14.21-cM (21.19-Mb) region on chromosome 8 at q11, flanked by D8S532 and D8S260. This region harbors RP1, which is known to cause autosomal dominant retinitis pigmentosa. Sequencing of the coding exons of RP1 showed mutations in all three families: two single-base deletions, c.4703delA and c.5400delA, resulting in a frame shift, and a 4-bp insertion, c.1606insTGAA, all causing premature termination of the protein. All affected individuals in these families are homozygous for the mutations. Parents and siblings heterozygous for the mutant allele did not show any signs or symptoms of RP. CONCLUSIONS: These results provide strong evidence that mutations in RP1 can result in recessive as well as dominant retinitis pigmentosa. The findings suggest that truncation of RP1 before the BIF motif or within the terminal portion results in a simple loss of RP1 function, producing a recessive inheritance pattern. In contrast, disruption of RP1 within or immediately after the BIF domain may result in a protein with a deleterious effect and hence a dominant inheritance pattern.

Chromosomes, Human, Pair 8↗
PubMed1993

Mapping the gene causing X-linked recessive nephrolithiasis to Xp11.22 by linkage studies.

X-linked recessive nephrolithiasis is associated with kidney stones and renal tubular dysfunction in childhood progressing to renal failure in adulthood. The primary defect causing this renal tubular disorder is unknown and determining the chromosomal location of the mutant gene would represent an important step toward defining the biochemical basis. We have performed linkage studies in 102 members (10 affected males, 47 unaffected males, 15 obligate heterozygote females, and 30 unaffected females) from five generations of one family. As genetic markers we used 10 cloned human X chromosome fragments identifying restriction fragment length polymorphisms and seven pairs of oligonucleotide primers identifying microsatellite polymorphisms. Linkage with the locus DXS255 was established with a peak LOD score = 5.91 at 3.6% recombination, thereby localizing the X-linked recessive nephrolithiasis gene to the pericentromeric region of the short arm of the X chromosome (Xp11.22). Multilocus analysis indicated that the mutant gene was distal to DXS255 but proximal to the Duchenne muscular dystrophy locus on Xp. Thus, the gene that causes X-linked recessive nephrolithiasis maps to the pericentromeric region of the short arm of the X chromosome (Xp11.22), and further characterization of this gene will help to elucidate the factors controlling renal tubular function and mineral homeostasis.

Adolescent↗