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Caries is a multifactorial disease and little is still known about the host genetic factors influencing susceptibility. Our previous genome-wide linkage scan has identified the interval 5q12.1–5q13.3 as linked to low caries susceptibility in Filipino families. Here we fine-mapped this region in order to identify genetic contributors to caries susceptibility. Four hundred and seventy-seven subjects from 72 pedigrees with similar cultural and behavioral habits and limited access to dental care living in the Philippines were studied. DMFT scores and genotype data of 75 single-nucleotide polymorphisms were evaluated in the Filipino families with the Family-Based Association Test. For replication purposes, a total 1,467 independent subjects from five different populations were analyzed in a case-control format. In the Filipino cohort, statistically significant and borderline associations were found between low caries experience and four genes spanning 13 million base pairs (PART1, ZSWIM6, CCNB1, and BTF3). We were able to replicate these results in some of the populations studied. We detected PART1 and BTF3 expression in whole saliva, and the expression of BTF3 was associated with caries experience. Our results suggest BTF3 may have a functional role in protecting against caries. Fil: Shimizu, T.. Nihon University of Dentistry; Japón Fil: Deeley, K.. University of Pittsburgh; Estados Unidos Fil: Briseño Ruiz, J.. University of Pittsburgh; Estados Unidos Fil: Faraco Junior, I. M.. University of Pittsburgh; Estados Unidos Fil: Poletta, Fernando Adrián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET.; Argentina Fil: Brancher, J. A.. Pontifical Catholic University of Paraná; Brasil Fil: Pecharki, G. D.. Pontifical Catholic University of Paraná; Brasil Fil: Küchler, E. C.. Universidade Federal Fluminense; Brasil Fil: Tannure, P. N.. Universidade Federal do Rio de Janeiro; Brasil Fil: Lips, A.. Universidade Federal do Rio de Janeiro; Brasil Fil: Vieira, T. C. S.. Universidade Federal Fluminense; Brasil Fil: Patir, A.. Istanbul Medipol Universit; Turquía Fil: Yildirim, M.. Istanbul University; Turquía Fil: Mereb, J. C.. Centro de Educación Médica e Investigaciones Clínicas “Norberto Quirno”; Argentina Fil: Resick, J. M.. University of Pittsburgh; Estados Unidos Fil: Brandon, C. A.. University of Pittsburgh; Estados Unidos Fil: Cooper, M. E.. University of Pittsburgh; Estados Unidos Fil: Seymen, F.. Istanbul University; Turquía Fil: Costa, M. C.. Universidade Federal do Rio de Janeiro; Brasil Fil: Granjeiro, J. M.. Universidade Federal Fluminense; Brasil Fil: Trevilatto, P. C.. Pontifical Catholic University of Paraná; Brasil Fil: Orioli, I. M.. Universidade Federal do Rio de Janeiro; Brasil. Centro de Educación Médica e Investigaciones Clínicas “Norberto Quirno”; Argentina Fil: Castilla, Eduardo Enrique. Instituto Oswaldo Cruz; Brasil. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET.; Argentina Fil: Marazita, M. L.. University of Pittsburgh; Estados Unidos Fil: Vieira, A. R.. University of Pittsburgh; Estados Unidos

Type IIB fast fibres are typically demonstrated in human skeletal muscle by histochemical staining for the ATPase activity of myosin heavy-chain (MyHC) isoforms. However, the monoclonal antibody specific for the mammalian IIB isoform does not detect MyHC IIB protein in man and MyHC IIX RNA is found in histochemically identified IIB fibres, suggesting that the IIB protein isoform may not be present in man; if this is not so, jaw-closing muscles, which express a diversity of isoforms, are likely candidates for their presence. ATPase histochemistry, immunohistochemistry polyacrylamide gel electrophoresis and in situ hybridization, which included a MyHC IIB-specific mRNA riboprobe, were used to compare the composition and RNA expression of MyHC isoforms in a human jaw-closing muscle, the masseter, an upper limb muscle, the triceps, an abdominal muscle, the external oblique, and a lower limb muscle, the gastrocnemius. The external oblique contained a mixture of histochemically defined type I, IIA and IIB fibres distributed in a mosaic pattern, while the triceps and gastrocnemius contained only type I and IIA fibres. Typical of limb muscle fibres, the MyHC I-specific mRNA probes hybridized with histochemically defined type I fibres, the IIA-specific probes with type IIA fibres and the IIX-specific probes with type IIB fibres. The MyHC IIB mRNA probe hybridized only with a few histochemically defined type I fibres in the sample from the external oblique; in addition to this IIB message, these fibres also expressed RNAs for MyHC I, IIA and IIX. MyHC IIB RNA was abundantly expressed in histochemical and immunohistochemical type IIA fibres of the masseter, together with transcripts for IIA and in some cases IIX. No MyHC IIB protein was detected in fibres and extracts of either the external oblique or masseter by immunohistochemistry, immunoblotting and electrophoresis. Thus, IIB RNA, but not protein, was found in the fibres of two different human skeletal muscles. It is believed this is the first report of the substantial expression of IIB mRNA in man as demonstrated in a subset of masseter fibres, but rarely in limb muscle, and in only a few fibres of the external oblique. These findings provide further evidence for the complexity of myosin gene expression, especially in jaw-closing muscles.

Caries is the most common chronic, multifactorial disease in the world today; and little is still known about the genetic factors influencing susceptibility. Our previous genome-wide linkage scan has identified five loci related to caries susceptibility: 5q13.3, 13q31.1, 14q11.2, 14q 24.3, and Xq27. In the present study, we fine mapped the 14q11.2 locus to identify genetic contributors to caries susceptibility. Four hundred seventy-seven subjects from 72 pedigrees with similar cultural and behavioral habits and limited access to dental care living in the Philippines were studied. An additional 387 DNA samples from unrelated individuals were used to determine allele frequencies. For replication purposes, a total of 1,446 independent subjects from four different populations were analyzed based on their caries experience (low versus high). Forty-eight markers in 14q11.2 were genotyped using TaqMan chemistry. Transmission disequilibrium test was used to detect over transmission of alleles in the Filipino families, and Chi-square, Fisher’s exact and logistic regression were used to test for association between low caries experience and variant alleles in the replication data sets. We finally assessed the mRNA expression of TRAV4 in the saliva of 143 study subjects. In the Filipino families, statistically significant associations were found between low caries experience and markers in TRAV4. We were able to replicate these results in the populations studied that were characteristically from underserved areas. Direct sequencing of 22 subjects carrying the associated alleles detects one missense mutation (Y30R) that is predicted to be probably damaging. Finally, we observed higher expression in children and teenagers with low caries experience, correlating with specific alleles in TRAV4. Our results suggest that TRAV4 may have a role in protecting against caries. Fil: Briseño Ruiz, Jessica. University of Pittsburgh; Estados Unidos Fil: Shimizu, Takehiko. Nihon University of Dentistry at Matsudo; Japón Fil: Deeley, Kathleen. University of Pittsburgh; Estados Unidos Fil: Dizak, Piper M.. University of Pittsburgh; Estados Unidos Fil: Ruff, Timothy D. University of Pittsburgh; Estados Unidos Fil: Faraco Jr., Italo M.. University of Pittsburgh; Estados Unidos Fil: Poletta, Fernando Adrián. Centro de Educación Médica e Investigaciones Clínicas “Norberto Quirno”; Argentina. Estudio Colaborativo Latino Americano de Malformaciones Congénitas. Buenos Aires; Argentina. Instituto de investigación en Porto Alegre; Brasil. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Brancher, Joao A.. Universidade Federal do Paraná; Brasil Fil: Pecharki, Giovana D.. Universidade Federal do Paraná; Brasil Fil: Kuchler, Erika C. University of Pittsburgh; Estados Unidos Fil: Tannure, Patricia N.. Universidade Federal do Rio de Janeiro; Brasil Fil: Lips, Andrea. Universidade Federal Fluminense; Brasil Fil: Vieira, Thays C. S.. Universidade Federal Fluminense; Brasil Fil: Patir, Asli. Istanbul Medipol University; Turquía Fil: Koruyucu, Mine. Istanbul University; Turquía Fil: Mereb, J. C.. Estudio Colaborativo Latino Americano de Malformaciones Congénita; Argentina Fil: Resick, Judith M.. University of Pittsburgh; Estados Unidos Fil: Brandon, Carla A.. University of Pittsburgh; Estados Unidos Fil: Letra, Ariadme. University of Texas Health Science Center at Houston; Estados Unidos Fil: Silva, Renato M.. University of Texas Health Science Center at Houston; Estados Unidos Fil: Cooper, Margaret E.. University of Pittsburgh; Estados Unidos Fil: Seymen, Figen. Istanbul University; Turquía Fil: Costa, Marcelo C.. Universidade Federal do Rio de Janeiro; Brasil Fil: Granjeiro, Jose M. Universidade Federal Fluminense; Brasil Fil: Trevilatto, Paula C.. Universidade Federal do Paraná; Brasil Fil: Orioli, Eeda M.. Instituto Nacional de Metrologia, Qualidade e Tecnologia; Brasil Fil: Castilla, Eduardo Enrique. Centro de Educación Médica e Investigaciones Clínicas “Norberto Quirno”; Argentina. Estudio Colaborativo Latino Americano de Malformaciones Congénitas. Buenos Aires; Argentina. Instituto de investigación en Porto Alegre; Brasil Fil: Marazita, Mary L.. University of Pittsburgh; Estados Unidos Fil: Vieira, Alexandre R.. University of Pittsburgh; Estados Unidos

Objective This exploratory research sought to extend the cleft phenotype by identifying movement-related soft tissue appearance changes in the midfacial region in individuals with cleft lip/palate or those with genetic susceptibility to cleft lip/palate (unaffected relatives). The cleft phenotype (clinically identified orofacial cleft or subclinical orbicularis oris defect) was hypothesized to be associated with movement related appearance changes in the midfacial region, e.g., with furrowing and dimpling during speech. Design Changes in the appearance of skin in the midfacial region, including a newly identified phenotypic feature, nasolabial fold (NLF) discontinuity, were described and compared across groups. Participants Individuals with cleft lip (n = 42), unaffected relatives of persons with a cleft (n = 57) and healthy controls (n = 41) were compared. Results Frequencies of NLF discontinuity differed across cleft, relative, and control groups. NLF discontinuities were observed more frequently in individuals with a cleft phenotype (overt cleft or previously identified orbicularis oris muscle defect) than in those with no underlying muscular defect (Fisher exact test, P = .014). Conclusion Results suggest that the appearance of facial soft tissue during movement of the midface is moderated at least in part by underlying cleft risk factors, indicating certain facial movements as candidate physical markers for extension of the cleft phenotype.

Nonsyndromic cleft lip with or without cleft palate (CL/P) is a common birth defect due to both genetic and environmental factors. Whorl lip print patterns are circular grooves on the central upper lip and/or the left and right lower lip. To determine if whorls are more common in families with CL/P than in controls, the Pittsburgh Orofacial Cleft Study collected lip prints from over 450 subjects, that is, individuals with CL/P, their relatives, and unrelated controls-from the U.S., Argentina, and Hungary. Using a narrow definition of lower-lip whorl, the frequency of whorls in the U.S. sample was significantly elevated in cleft individuals and their family members, compared to unrelated controls (14.8% and 13.2% vs. 2.3%; P = 0.003 and 0.001, respectively). Whorls were more frequent in CL/P families from Argentina than in CL/P families from the U.S. or Hungary. If these results are confirmed, whorl lip print patterns could be part of an expanded phenotypic spectrum of nonsyndromic CL/P. As such, they may eventually be useful in a clinical setting, allowing recurrence risk calculations to incorporate individual phenotypic information in addition to family history data.

Background Cancer and congenital malformations occasionally may have acommon etiology. The authors investigated whether families with one or more members affected by orofacial clefts (that is, families segregating orofacial clefts) had an increased cancer incidence when compared with control families. Methods The authors assessed 75 white families with nonsyndromic cleft lip with or without cleft palate (CL/P) and 93 white control families regarding a history of cancer. They used χ 2 and Fisher exact tests to determine significant differences. They then performed molecular studies with genes in which mutations have been independently associated with both cancer and craniofacial anomalies in a total of 111 families with CL/P. Results The families with CL/P reported a family history of cancer more often than did control families ( P P P = .003), leukemia ( P = .005), breast ( P = .009), prostate ( P = .01), skin ( P = .01), lung ( P = .02) and liver ( P = .02). The authors detected overtransmission of AXIS inhibition protein 2 (AXIN2) in CL/P probands ( P = .003). Conclusion Families segregating CL/P may have an increased susceptibility to cancer, notably colon cancer. Furthermore, AXIN2, a gene that when mutated increases susceptibility to colon cancer, also is associated with CL/P. Clinical Implications People who are at a higher risk of developing disease need to adopt a healthier lifestyle, including avoiding exposure to risk factors that may interact with their genotypes.

Summary: This study describes the myosin composition of extrafusal and intrafusal muscle fibers found in the human thyroarytenoid (TA) and sternohyoid (control) muscles. We sought to determine the presence of muscle spindles in the TA muscle, and to identify unusual extrafusal fiber types, using the commonly accepted approach of tissue stainng with myosin isoform specific antibodies. Extrafusal fibers are organized into motor units, which subsequently produce muscle movement, whereas intrafusal fibers compose muscle spindles, the primary stretch receptor that provides afferent (feed back) information to the nervous system for regulation of motor unit length and tonicity. Immunohistochemical identification of muscle spindles was con-firmed in sternohyoid, but not in TA samples; however, some extrafusal fibers contained tonic myosin. These results indicate that human TA muscle functions similar to some mammalian extraocular muscle, performing unloaded (non-weight bearing) contractions without afferent information from native muscle spindles.

Summary: The human posterior cricoarytenoid (PCA) muscle is divided into two compartments, the vertical and horizontal bellies, which contain differences in their myosin heavy chain (MyHC) composition. Using immunohistochemical techniques on whole PCA samples, this study provides a more thorough description of the fiber type composition of entire bellies of the PCA. Four patients provided complete PCA samples containing both compartments of their right and left sides; two with unilaterally immobilized vocal folds. The horizontal belly had 80% slow (type I) fibers and 20% fast (type II) fibers. The vertical belly contained equal amounts of slow and fast fibers (∼55%:45%); clearly distinguishing between two compartments. Atrophy of muscle fibers and fiber type grouping were also present in both normal and affected subjects; providing no clear confirmation of the clinical findings of vocal fold immobilization. Further study of the PCA muscle from patients with unilaterally immobilized vocal folds is needed.

While human masseter muscle is known to have unusual co-expression of myosin heavy-chain proteins, cellular kinetics of individual fibers has not yet been tested. Here we examine if myosin heavy-chain protein content is closely correlated to fiber-shortening speed, as previously reported in other human muscles, or if these proteins do not correlate well to shortening speeds, as has been demonstrated previously in rat muscle. Slack-test recordings of single, skinned human masseter fibers at 15°C revealed maximum shortening velocities generally slower and much more variable than those recorded in human limb muscle. The slowest fiber recorded had a maximum shortening velocity (V0) value of 0.027 muscle lengths ·s-1, several times slower than the slowest type I fibers previously measured in humans. By contrast, human limb muscle controls produced V0 measurements comparable with previously published results. Analysis by gel electrophoresis found 63% of masseter fibers to contain pure type I MyHC and the remainder to co-express mostly type I in various combinations with IIA and IIX isoforms. Vo in masseter fibers forms a continuum in which no clear relationship to MyHC isoform content is apparent.

Myosin description in human laryngeal muscles is incomplete, but evidence suggests the presence of type I, IIA, IIX, and tonic myosin heavy chain (MHC) fibers. This study describes the unloaded shortening velocity (V0) of chemically skinned laryngeal muscle fibers measured by the slack test method in relation to MHC content. Skeletal fibers from human laryngeal and limb muscle biopsy specimens were obtained for determination of V0, and subsequently, glycerol–sodium dodecyl sulfate–polyacrylamide gel electrophoresis was used to determine the MHC isoform content. The fibers from human limb muscle had shortening speeds similar to those in previous reports on human skeletal fibers. Type I, IIA, and IIX fibers of laryngeal muscle had shortening speeds similar to those of fibers from limb muscle, but laryngeal fibers with heterogeneous MHC expression had a wide range of shortening speeds, some being nearly twice as fast as limb fibers. In addition, MHC isoform bands from human extraocular muscle comigrated with some bands from laryngeal muscle — a finding suggesting that extraocular myosin may also be expressed.