The identification of malaria in paleopathology-An in-depth assessment of the strategies to detect malaria in ancient remains

The comprehensive analyses of human remains from various places and time periods, either by immunological or molecular approaches, provide circumstantial evidence that malaria tropica haunted humankind at least since dynastic ancient Egypt. Here we summarize the "actual state-of-the-art" of these bio-molecular investigations and offer a solid basis for the discussion of the paleopathology of malaria in human history.

Reconstructing the life of an unknown (ca. 500 years-old South American Inca) mummy--multidisciplinary study of a Peruvian Inca mummy suggests severe Chagas disease and ritual homicide

The paleopathological, paleoradiological, histological, molecular and forensic investigation of a female mummy (radiocarbon dated 1451–1642 AD) provides circumstantial evidence for massive skull trauma affecting a young adult female individual shortly before death along with chronic infection by Trypanosoma cruzi (Chagas disease). The mummy (initially assumed to be a German bog body) was localized by stable isotope analysis to South America at/near the Peruvian/Northern Chilean coast line. This is further supported by New World camelid fibers attached to her plaits, typical Inca-type skull deformation and the type of Wormian bone at her occiput. Despite an only small transverse wound of the supraorbital region computed tomography scans show an almost complete destruction of face and frontal skull bones with terrace-like margins, but without evidence for tissue reaction. The type of destruction indicates massive blunt force applied to the center of the face. Stable isotope analysis indicates South American origin: Nitrogen and hydrogen isotope patterns indicate an extraordinarily high marine diet along with C4-plant alimentation which fits best to the coastal area of Pacific South America. A hair strand over the last ten months of her life indicates a shift to a more “terrestric” nutrition pattern suggesting either a move from the coast or a change in her nutrition. Paleoradiology further shows extensive hypertrophy of the heart muscle and a distended large bowel/rectum. Histologically, in the rectum wall massive fibrosis alternates with residual smooth muscle. The latter contains multiple inclusions of small intracellular parasites as confirmed by immunohistochemical and molecular ancient DNA analysis to represent a chronic Trypanosoma cruzi infection. This case shows a unique paleopathological setting with massive blunt force trauma to the skull nurturing the hypothesis of a ritual homicide as previously described in South American mummies in an individual that suffered from severe chronic Chagas disease.

Revisiting the harem conspiracy and death of Ramesses III: anthropological, forensic, radiological, and genetic study

OBJECTIVE

To investigate the true character of the harem conspiracy described in the Judicial Papyrus of Turin and determine whether Ramesses III was indeed killed.

DESIGN

Anthropological, forensic, radiological, and genetic study of the mummies of Ramesses III and unknown man E, found together and taken from the 20th dynasty of ancient Egypt (circa 1190-1070 BC).

RESULTS

Computed tomography scans revealed a deep cut in Ramesses III's throat, probably made by a sharp knife. During the mummification process, a Horus eye amulet was inserted in the wound for healing purposes, and the neck was covered by a collar of thick linen layers. Forensic examination of unknown man E showed compressed skin folds around his neck and a thoracic inflation. Unknown man E also had an unusual mummification procedure. According to genetic analyses, both mummies had identical haplotypes of the Y chromosome and a common male lineage.

CONCLUSIONS

This study suggests that Ramesses III was murdered during the harem conspiracy by the cutting of his throat. Unknown man E is a possible candidate as Ramesses III's son Pentawere.

Graveyards - special landfills

Graveyards have been a matter of controversial debate for many years in terms of the risk they pose to the environment. However, literature data are inconclusive and there are no systematic studies available from modern graveyards with special reference to soil found in the vicinity of the coffin. To our knowledge, the present study is the first to systematically investigate a comprehensive exhumation series (involving 40 graves) in order to determine burial-related changes in matter and element content. Human burials lead to the accumulation of certain elements, with higher than normal levels of N, C, Zn, Ba, Ca and Na being observed in soils below coffins. Decomposition material inside coffins has much higher levels of heavy metals and alkaline elements than the surrounding soil. However, the major problem observed was the large quantity of synthetic bedding material which is more likely to lead to the formation of adipocere under the moist conditions given. Adipocere formation, which is the result of the anaerobic bacterial hydrolysis of fat, is known to interrupt the natural decomposition process and delay the post-mortem release of elements. We assume that once the inhumed matter has completely decomposed, much higher than normal levels of pollutants will be released into and have an ecological effect on the soil and water environment.

Enlightening the past: analytical proof for the use of Pistacia exudates in ancient Egyptian embalming resins

Mastic, the resinous exudate of the evergreen shrub Pistacia lentiscus, is frequently discussed as one of the ingredients used for embalming in ancient Egypt. We show the identification of mastic in ancient Egyptian embalming resins by an unambiguous assignment of the mastic triterpenoid fingerprint consisting of moronic acid, oleanonic acid, isomasticadienonic and masticadienonic acid through the consolidation of NMR and GC/MS analysis. Differences in the observed triterpenoid fingerprints between mummy specimens suggest that more than one plant species served as the triterpenoid resin source. Analysis of the triterpenoid acids of ancient embalming resin samples in the form of their methyl- and trimethylsilyl esters is compared. In addition we show a simple way to differentiate between residues of mastic from its use as incense during embalming or from direct mastic application in the embalming resin.

Epigenetic alterations by methylation of RASSF1A and DAPK1 promoter sequences in mammary carcinoma detected in extracellular tumor DNA

Novel strategies for early detection of breast cancer, the most common and second most lethal cancer in women, are urgently needed. Silencing tumor suppressor genes via DNA methylation has established hypermethylation as one of the most frequent molecular alterations that may initiate and drive many types of human neoplasia including breast cancer. Detecting such epigenetic changes in DNA derived not only from tumor tissue, but also from bodily fluids, may be a promising target for the molecular analysis of cancer. In this study we examined serum, a readily accessible bodily fluid known to contain neoplastic DNA, from individuals with breast carcinoma. Using sensitive methylation-specific polymerase chain reaction, we searched for aberrant promoter hypermethylation of two normally nonmethylated genes: RAS association domain family member 1A (RASSF1A) and death-associated protein kinase 1 (DAPK1) in 26 patients with breast cancer, 16 patients with benign breast diseases, and 12 age-matched healthy controls. Hypermethylation of at least one gene was detected in 25/26 (96%) cancer patients, in 7/16 (43%) cases with benign breast diseases, and only 1/12 (8%) control subjects. Furthermore, methylation of both genes was found to be associated with ductal type of breast carcinoma. RASSF1A was hypermethylated in 18/26 cases (69%) and DAPK1 in 23/26 (88%). However, DAPK1 promoter methylation was more pronounced, as 12/23 DAPK1 methylated cases (52%) were strongly methylated (>75%) compared to the weaker methylation of RASSF1A (none of the cases with methylation at the level of >75%). These findings, if confirmed in studies of extended cohorts, may lead to useful clinical application in early diagnosis of breast cancer and better management of the neoplastic disease.

Ancestry and pathology in King Tutankhamun's family

CONTEXT

The New Kingdom in ancient Egypt, comprising the 18th, 19th, and 20th dynasties, spanned the mid-16th to the early 11th centuries bc. The late 18th dynasty, which included the reigns of pharaohs Akhenaten and Tutankhamun, was an extraordinary time. The identification of a number of royal mummies from this era, the exact relationships between some members of the royal family, and possible illnesses and causes of death have been matters of debate.

OBJECTIVES

To introduce a new approach to molecular and medical Egyptology, to determine familial relationships among 11 royal mummies of the New Kingdom, and to search for pathological features attributable to possible murder, consanguinity, inherited disorders, and infectious diseases.

DESIGN

From September 2007 to October 2009, royal mummies underwent detailed anthropological, radiological, and genetic studies as part of the King Tutankhamun Family Project. Mummies distinct from Tutankhamun's immediate lineage served as the genetic and morphological reference. To authenticate DNA results, analytical steps were repeated and independently replicated in a second ancient DNA laboratory staffed by a separate group of personnel. Eleven royal mummies dating from circa 1410-1324 bc and suspected of being kindred of Tutankhamun and 5 royal mummies dating to an earlier period, circa 1550-1479 bc, were examined.

MAIN OUTCOME MEASURES

Microsatellite-based haplotypes in the mummies, generational segregation of alleles within possible pedigree variants, and correlation of identified diseases with individual age, archeological evidence, and the written historical record.

RESULTS

Genetic fingerprinting allowed the construction of a 5-generation pedigree of Tutankhamun's immediate lineage. The KV55 mummy and KV35YL were identified as the parents of Tutankhamun. No signs of gynecomastia and craniosynostoses (eg, Antley-Bixler syndrome) or Marfan syndrome were found, but an accumulation of malformations in Tutankhamun's family was evident. Several pathologies including Köhler disease II were diagnosed in Tutankhamun; none alone would have caused death. Genetic testing for STEVOR, AMA1, or MSP1 genes specific for Plasmodium falciparum revealed indications of malaria tropica in 4 mummies, including Tutankhamun's. These results suggest avascular bone necrosis in conjunction with the malarial infection as the most likely cause of death in Tutankhamun. Walking impairment and malarial disease sustained by Tutankhamun is supported by the discovery of canes and an afterlife pharmacy in his tomb.

CONCLUSION

Using a multidisciplinary scientific approach, we showed the feasibility of gathering data on Pharaonic kinship and diseases and speculated about individual causes of death.

Otoferlin interacts with myosin VI: implications for maintenance of the basolateral synaptic structure of the inner hair cell

Otoferlin has been proposed to be the Ca(2+) sensor in hair cell exocytosis, compensating for the classical synaptic fusion proteins synaptotagmin-1 and synaptotagmin-2. In the present study, yeast two-hybrid assays reveal myosin VI as a novel otoferlin binding partner. Co-immunoprecipitation assay and co-expression suggest an interaction of both proteins within the basolateral part of inner hair cells (IHCs). Comparison of otoferlin mutants and myosin VI mutant mice indicates non-complementary and complementary roles of myosin VI and otoferlin for synaptic maturation: (i) IHCs from otoferlin mutant mice exhibited a decoupling of CtBP2/RIBEYE and Ca(V)1.3 and severe reduction of exocytosis. (ii) Myosin VI mutant IHCs failed to transport BK channels to the membrane of the apical cell regions, and the exocytotic Ca(2+) efficiency did not mature. (iii) Otoferlin and myosin VI mutant IHCs showed a reduced basolateral synaptic surface area and altered active zone topography. Membrane infoldings in otoferlin mutant IHCs indicated disturbed transport of endocytotic membranes and link the above morphological changes to a complementary role of otoferlin and myosin VI in transport of intracellular compartments to the basolateral IHC membrane.

Fronto-ethmoidal encephalocele in a historical skull with artificial deformation and no signs of chronic elevated intracranial pressure

The intentional deformation of human skulls in the living being was one of the most curious rituals performed in historical and ancient times. It is thought that these practices cause chronic elevated intracranial pressure and subsequent symptoms of cognitive impairment. In this report, we examine such an artificially deformed skull dating from the sixteenth century that in addition shows a fronto-ethmoidal encephalocele. However, although the mild encephalocele was already manifest at birth and deformation practices were performed over years, the encephalocele did not progress into a more severe status. We conclude that the intentional deformation of skulls does not lead to chronic elevated intracranial pressure and mental retardation.

Lack of Tff3 peptide results in hearing impairment and accelerated presbyacusis

Tff peptides are secreted mainly by the gastrointestinal epithelial cells and their primary role is maintaining normal structure and function of mucous epithelia. Ongoing studies on their expression pattern have disclosed other sites of their synthesis thus revealing additional physiological functions in the organism. Here we present new data about Tff3 expression in the cochlea of the rodent inner ear. On the basis of RT-PCR we describe the presence of Tff3 transcripts in both, a mouse cDNA library isolated from whole cochleae from postnatal days 3-15 (P3-P15), and also in cochlear tissue. By using a riboprobe for the fragment containing exon 1, 2 and 3 of Tff3, in situ hybridization, localized Tff3 signals in neurons of spiral ganglion and vestibular organ. We did not observe any abnormalities in the middle ear of Tff3 knock-out mice, neither did histological examination of the inner ear indicate any gross morphological changes in the cochlea. However, ABR (auditory evoked brain stem responses) audiograms revealed that the Tff3 knock-out animals show an accelerated presbyacusis and a hearing loss of about 15 dB at low frequencies increasing to 25 dB loss at higher frequencies. These findings suggest that Tff3 could play a role in neurosensory signaling. Further studies are needed to clarify this new function in the auditory system.

Refinement of the MYP3 locus on human chromosome 12 in a German family with Mendelian autosomal dominant high-grade myopia by SNP array mapping

Myopia, or short-sightedness, is the most common form of vision disorder worldwide. Higher levels of myopia, usually defined as an axial eye length of >26 mm or a refractive error of < -5.00 diopters are often designated as 'pathologic' myopia, because of the predisposition to develop further eye disorders such as retinal detachment, macular degeneration, cataract, or glaucoma. Many distinct forms of autosomal dominant non-syndromic high-grade myopia are described in humans. While the underlying chromosomal locations and critical disease intervals have been identified and located to physical map positions, the gene defects and causative mutations responsible for autosomal dominant myopia remain elusive to date. Examination of a German six-generation kindred by 10K whole genome chips led to the identification of a 19-cM map segment as being the most likely familial myopia candidate region spanning from chromosomal band 12q14.3 to 12q21.31 (MYP3). In our family, a maximum multi-point LOD score of 3.9 was obtained between rs1373877 and rs717996. The recombination breakpoints in this family and the interval of the originally reported German/Italian family defining the MYP3 locus on chromosome 12 (OMIM 603221, two-point LOD score 3.85 for markers D12S1706 and D12S327 at 12q21-23) allowed us to significantly refine a minimum consensus region. This new composite region is located between microsatellite marker D12S1684 at 75.8 K and SNP_A-1509586 (alias rs717996) at position 82,636,288 bp, and narrows the original 30.1 cM of the MYP3 interval to 6.8 cM. The refined MYP3 interval allowed us to restrict the list of database-indexed genes to 25, several of which are promising MYP3 candidates based on similarities with genes and proteins involved in vision physiology and eye disease. While autosomal dominant high-grade myopia is recognized to be genetically heterogeneous, our results suggest genetic homogeneity of the MYP3-based condition in families that share the same ethnic and geographical background. The future identification of this MYP3 gene may provide insights into the pathophysiology of myopia and eye development.

Morphometric analysis of untreated adult skulls in syndromic and nonsyndromic craniosynostosis

The aim of this study was to perform a morphometric analysis of untreated adult skulls displaying syndromic and nonsyndromic craniosynostosis. We analyzed, in detail, 42 adult craniosynostoses (18 scaphocephaly, 11 anterior plagiocephaly, 2 trigonocephaly, 9 oxycephaly, and 2 brachycephaly) from archeological (three skulls) and pathoanatomical samples (39 skulls). The univariate and bivariate measurements from the pathological skulls were compared with 40 anatomical skulls with normal cranial vault morphology. Bony signs of chronic elevated intracranial pressure (ICP) are (1) diffuse beaten copper pattern, (2) dorsum sellae erosion, (3) suture diastasis, and (4) abnormalities of venous drainage that particularly affect the sigmoid-jugular sinus complex. The mean cranial length was significantly greater in scaphocephaly than in anatomical skulls (20.3 vs 18.0 cm), and the sagittal suture was also longer (14.3 vs 11.8 cm). There were three types of suture course in the bregma region in scaphocephaly: anterior spur (28%), normal configuration (61%), and posterior spur (11%). The plagiocephaly measurements showed nonsignificant differences, and there was no correlation between the length of the anterior and middle skull base (ipsilateral anterior-posterior shortening of the skull) and incomplete or complete suture synostosis. Bony signs of chronic elevated ICP were found in 82% of cases of oxycephaly and brachycephaly. In three such cases of oxycephaly, we found a marked (1.8-2.1 cm) elevation of bregma region. One skull (Saethre-Chotzen syndrome) yielded human DNA sufficient for polymerase chain reaction (PCR)-based amplification procedures. Mutation analyses in the FGFR3 gene revealed nucleotide alterations located in the mutational hot spot at amino acid residue 250 (g.C749). The mean cranial length in adult scaphocephaly was 12% greater than anatomical skulls. A unilateral complete or incomplete coronal synostosis can be found with or without plagiocephalic deformation. Elevation of the bregma region is a bony sign of chronic elevated ICP. These data on adult craniosynostosis could be of interest for physicians dealing with craniosynostotic children.

Cytokine regulation of the trefoil factor family binding protein GKN2 (GDDR/TFIZ1/blottin) in human gastrointestinal epithelial cells

Trefoil factor family (TFF) peptides are major secretory products of mucous epithelia and play a multifunctional role in cytoprotection, apoptosis, and immune response. Recently, a TFF2-binding protein was discovered in mice and named blottin. It is down-regulated in gastric cancer (GDDR), abundant in human gastric surface (TFIZ1) and its similarity to gastrokine-1 led to the gene's name GKN2. To investigate the mode of GKN2 regulation activity of a luciferase reporter gene, controlled by the GKN2 promoter, was monitored upon treatment with various pro-inflammatory (TNF-alpha, IL-1beta, IL-6, IFN-gamma) and anti-inflammatory (TGF-beta1) cytokines using gastric (AGS, KATO III) and colonic (HT-29) cell lines. To assess the direct role of transcription factors (NFkappaB, HNF-3beta, hGATA6) in regulating GKN2 we performed transient co-transfection of their expression plasmids and the reporter gene construct. GKN2 gene was down-regulated by pro-inflammatory cytokines in all tested cell lines while up-regulated by TGF-beta1 only in the colonic cell line. GKN2 expression was significantly reduced in both gastric adenocarcinoma cell lines by the active form of NFkappaB transcription factor, whereas in the colonic cell line an up-regulation was noticed. Down-regulation by IL-6 was mediated by C/EBPbeta transcription factor in case of HT-29 but not of KATO III cells. We conclude that the regulation of GKN2 parallels that of TFF genes, indicating that together they may play an important role in maintaining the homeostasis of the gastrointestinal tract.

Population haplotypes of exon ORF15 of the retinitis pigmentosa GTPase regulator gene in Germany : implications for screening for inherited retinal disorders

BACKGROUND

Mutations in exon ORF15 of the retinitis pigmentosa GTPase regulator gene (RPGR) within chromosomal region Xp21.1 are a significant cause of a number of retinal disorders. The high mutation rate is ascribed to the highly repetitive, purine-rich tracts within the exon ORF15 sequence. Importantly, all exon ORF15 mutations observed to date represent protein-truncating mutations (nonsense and frameshift mutations). Because of its repetitive motifs, mutation screening of the hot-spot region by direct DNA sequencing is a technically challenging task.

METHODS

We devised a screening strategy for exon ORF15 mutations that reserves DNA sequencing for precise sizing and base-order assessment of detected mutations. The screening strategy is based on a PCR/restriction fragment length polymorphism (RFLP) analysis of exon ORF15 and comparison with population-specific RFLP haplotypes. The latter were constructed from PCR/RFLP analysis of DNA samples from 100 healthy German male individuals. Mutational alterations of normal RFLP haplotype patterns were predicted.

RESULTS

Six distinct RFLP haplotypes (founder alleles H1-H6) were observed with frequencies ranging from 2% to 63%. All natural variations of exon ORF15 were in-frame alterations ranging in size between 3bp and 36bp. Prediction of mutation-specific RFLP patterns indicated a high detection rate of mutations.

CONCLUSION

A new strategy has been developed using routine protocols for mutation screening of difficult-to-sequence, highly repetitive exon ORF15 of the RPGR gene in a German population.

Genetic heterogeneity of deafness phenotypes linked to DFNA4

Mutations in the heavy chain of the class II nonmuscle myosin, MYH14, cause autosomal dominant hearing loss in families linked to the DFNA4 locus. Consistent with this discovery, we identified an S120L mutation in MYH14 in a large German family segregating deafness that links to DFNA4. However, complete screening of the American family that originally defined the DFNA4 locus revealed no mutations in this gene. Furthermore, haplotyping of a single nucleotide polymorphism (SNP) 5' to MYH14 excludes this gene from the critical region in this family. Our results imply that mutations in another gene result in deafness at the DFNA4 locus. The newly defined candidate region encompasses a region of approximately 19 cM. Several candidate genes have been screened for disease-causing mutations.

Mutational risk in highly repetitive exon ORF15 of the RPGR multidisease gene is not associated with haplotype background

Exon ORF15 is an alternative exon in the retinitis pigmentosa GTPase regulator (RPGR) gene containing a highly repetitive, purine-rich internal region. It constitutes a mutational hot spot giving rise to a group of heterogeneous X-linked retinal disorders. We sought to determine whether non-pathogenic substitutions and sequence length variations in the repetitive sequence have an influence on the risk of pathogenic exon ORF15 mutations. The type and distribution of exon ORF15 polymorphisms were assessed by genotyping 107 healthy German males using standard procedures. Polymorphisms were grouped into haplotypes and their frequencies determined in normal controls and previously analyzed patients with X-linked retinitis pigmentosa (XLRP). In the control group we identified 6 complex variants of the most common, ancestral exon ORF15 allele corresponding to the GenBank reference sequence (accession no. AF286472). Exon ORF15 mutations in XLRP patients were associated with the ancestral allele in 75% of affected cases. Four of the most recent founder haplotypes termed H3, H4, H6 and H7 were not identified in the patient samples. Our analysis and review of polymorphism data from the published literature suggests the presence of common exon ORF15 haplotypes in the European population. While the mutational risk in the RPGR gene appears not to be altered by the haplotype background, exon ORF15 haplotype analysis may be useful for tracing the evolutionary history of RP3-associated diseases.

Autoimmune retinopathy with RPE hypersensitivity and 'negative ERG' in X-linked hyper-IgM syndrome

PURPOSE

To report the clinical, electrophysiological, and immunological features of a patient with X-linked hyper-IgM immunodeficiency syndrome type 1 (HIGM1) accompanied by a novel type of autoimmune retinopathy, including retinal pigment epithelium (RPE) hypersensitivity.

METHODS

Comprehensive ophthalmological examinations, electrophysiological function testing, and inquiries into the immunological status of a 13-year-old presenting with subacute loss of vision in association with a molecularly confirmed diagnosis of HIGM1 were performed. The patient was genotyped by a PCR-based sequence tag content mapping strategy to define the genetic defect within the causative X-HIM gene TNFSF5. Since conventional allogenic bone marrow transplantation has been reported to cure HIGM1, a peripheral blood stem-cell transplantation was performed.

RESULTS

(1) The patient's reduced visual acuity included prolonged dark adaptation and visual field constriction. Electrophysiology revealed a 'negative ERG' indicating post-receptoral dysfunction. (2) Initial immunological examination of the patient's serum identified abnormal antibody activity with components of the photoreceptors and the inner nuclear layer. The patient later developed indications of RPE hypersensitivity. A massively reduced light-peak to dark-trough ratio of the EOG slow oscillations (L/D ratio) corresponded to impaired RPE-photoreceptor complex function. (3) Molecular genetic analyses revealed the patient to be nullizygous for the tumor necrosis factor ligand member 5 gene (TNFSF5; CD40LG). A large chromosomal deletion of approximately 27.6-32.3 kb in size was identified in Xq26. (4) The transplant with its associated immunomodulation appeared to worsen rather than improve the patient's condition.

CONCLUSIONS

The fundus appearance and electrophysiological function testing revealed indications of atypical retinal degeneration. However, the clinical course and the serological findings were consistent with those of ocular autoimmunity involving both antiretinal activity and RPE hypersensitivity. In this case, peripheral stem-cell transfusion with its associated chemotherapy failed to benefit the patient's vision; indications of autoimmunity appeared to increase following this treatment.

A genetic perspective on myopia

Myopia is a refractive error of the eye that has a significant socioeconomic impact due to its increasing prevalence and the fact that it causes visual impairment. Its aetiology is complex and is likely to involve the interaction of environmental and genetic influences. Tight environmental influence is exemplified by defocus-induced myopia produced in animal models, while genetic factors predominate in familial occurrence of myopia with a Mendelian inheritance pattern. The involvement of numerous mediators, such as cytokines, neurotransmitters and transcription factors, in myopia development has been indicated through various lines of investigation, particular interest focussing on scleral extracellular matrix proteins and developmental genes of the eye. As high-throughput technology for large-scale genotyping and RNA expression analysis enters the field of myopia research, a productive avenue will open up for deciphering the aetiological heterogeneity of myopia and the biological pathways underlying its development.

Multifocal oscillatory potentials in CSNB1 and CSNB2 type congenital stationary night blindness

We evaluated the function of the inner retina in patients with congenital stationary night blindness of the complete (CSNB1) and the incomplete type (CSNB2) by recording multifocal oscillatory potentials (mf-OPs). The VERIS system was used to record mf-OPs from 61 areas of the central retina from 5 CSNB1 patients (4 with NYX gene mutation), 6 CSNB2 patients (2 with CACNA1F mutation) and 11 control subjects. For each subject group, the first- and second-order kernel responses for one eye were analysed and the amplitudes and implicit times of their major components compared to 5 concentric rings centred on the fovea. In CSNB1 patients, the mf-OP peak amplitudes of the first-order kernel responses showed a significant reduction of the first peak without significant reduction of the second, whereas in CSNB2 both peak amplitudes were barely discernable from noise for all eccentricities. In the second-order kernel, the third peak was reduced in CSNB1 patients, and again not discernable from noise in CSNB2 patients. The difference in amplitude between the control and CSNB1 groups was significant for the late components of the first- and the second-order kernel. Implicit times were not significantly altered. The difference in mf-OP amplitude between CSNB1 and CSNB2 patients reflects the different molecular mechanisms underlying the two types of disease, which differentially affect the postreceptoral pathways of cone signal processing. The well-preserved peak 2 amplitudes of first-order mf-OPs and peak 3 amplitudes of second-order mf-OPs in CSNB1 patients point to a major impact of OFF-pathway components on these responses which are not present in CSNB2 patients. In conclusion, our results show that CSNB1 and CSNB2 are two different types of disease, not only on a genetic but also on a pathophysiological level.

Reduced expression of connexin 31.1 in larynx cancer is not caused by GJB5 mutations

Lack of regular cell-cell interaction is one major cause for neoplastic growth and metastasis. In head and neck squamous cell carcinomas a 10-fold down-regulation of connexin31.1 (GJB5) as well as mutations in the TGF-beta-receptor-II were reported. We performed mutation screenings in GJB5 and the TGF-beta-receptor-II poly(10)adenine hot spot employing larynx cancer samples of 10 patients. Variable length of the TGF-beta-receptor-II adenine homopolymer in controls and tumours indicate a high slippage error rate of the DNA polymerases rendering mutational analyses inconsistent. Lack of GJB5 mutations in the entire tumour collection suggests that this gene is not primarily involved in laryngeal tumorigenesis.

Paleopathological examination of medieval spines with exceptional thoracic kyphosis most likely secondary to spinal tuberculosis. Historical vignette

Spinal tuberculosis (TB) infrequently involves more than one to three vertebrae, and kyphotic angulation of greater than 30 degrees is rare in paleopathological specimens and clinical studies. The authors describe findings obtained in two spines (dating from the Early and Late Middle Ages). Spinal TB was present in both as well as sharply angulated kyphosis (approximately 180 degrees) resulting from complete destruction of five and seven vertebral bodies, respectively. In these two specimens obtained in individuals older than 12 years of age at the time of death we observed no involvement of the disease in posterior vertebral elements, and the laminae showed osseous fusion without signs of infection. The osseous diameter of the spinal canal was not narrowed in either case. These findings are discussed in the context of modern medical knowledge and paleopathological and genetic examinations.

PCR-Induced Sequence Alterations Hamper the Typing of Prehistoric Bone Samples for Diagnostic Achondroplasia Mutations

Achondroplasia (ACH) is a skeletal disorder (MIM100800) with an autosomal dominant Mendelian inheritance and complete penetrance. Here we report the screening of ancient bone samples for diagnostic ACH mutations. The diagnostic G-->A transition in the FGFR3 gene at cDNA position 1138 was detected in cloned polymerase chain reaction (PCR) products obtained from the dry mummy of the Semerchet tomb, Egypt (first dynasty, approximately 4,890-5,050 BP [before present]), and from an individual from Kirchheim, Germany (Merovingian period, approximately 1,300-1,500 BP), both of which had short stature. However, these mutations were also reproducibly observed in four ancient control samples from phenotypically healthy individuals (false-positives), rendering the reliable molecular typing of ancient bones for ACH impossible. The treatment of a false-positive DNA extract with uracil N-glycosylase (UNG) to minimize type 2 transitions (G-->A/C-->T) did not reduce the frequency of the false-positive diagnostic ACH mutations. Recently, it was suggested that ancient DNA extracts may induce mutations under PCR. Contemporary human template DNA from a phenotypically healthy individual was therefore spiked with an ancient DNA extract from a cave bear. Again, sequences with the diagnostic G-->A transition in the FGFR3 gene were observed, and it is likely that the false-positive G-->A transitions result from errors introduced during the PCR reaction. Amplifications in the presence of MnCl(2) indicate that position 1138 of the FGFR3 gene is particularly sensitive for mutations. Our data are in line with previously published results on the occurrence of nonrandom mutations in PCR products of contemporary human mitochondrial HVRI template DNA spiked with ancient DNA extracts.

[Paraganglioma in the area of the head and neck. A review of molecular genetic research]

Paragangliomas of the head and neck region are usually benign tumors that develop from chemoreceptors of paraganglionic origin in the majority of patients. These receptors play an important role in sensing and regulation of the blood CO(2) level. Genetic alterations in the mitochondrial enzyme complex II (SDH), which is involved in respiratory chain and citric acid cycle reactions, have been shown to lead to sporadic as well as familial cases of these tumors. The gene encoding the subunit SDHD shows mutations in up to 50% of these cases. In addition, loss of heterozygosity (LOH) was demonstrated in these tumor samples and has been shown to be connected with oncogenesis of paragangliomas. Thus, SDHD is the first known tumor suppressor gene encoding a mitochondrial protein. In this article we summarize the current state of knowledge concerning the development of paragangliomas.

Refinement of the DFNA4 locus to a 1.44�Mb region in 19q13.33

Many forms of autosomal dominant non-syndromic hearing impairment are known. While the underlying gene defects and causative mutations have been discovered for some forms, the gene responsible for DFNA4 has remained elusive to date. Examination of a German four-generation kindred led to the identification of a 1.44 Mb map segment in contig NT_011109 as being the most likely DFNA4 candidate region in 19q13.33. The recombination breakpoints in this family and the intervals of two previously reported DFNA4 families allowed us to delineate a minimum consensus region between the markers D19S879 and D19S246. In our family, a maximum two-point LOD score of 4.5 was obtained at theta = 0 for the marker D19S867. Within the refined DFNA4 interval the public databases list more than 50 genes, from which several appear to be promising DFNA4 candidates due to similarities with animal models and with other causative genes involved in hearing disability.

Cytotoxic activity of natural killer cells lacking killer-inhibitory receptors for self-HLA class I molecules against autologous hematopoietic stem cells in healthy individuals

Killer-inhibitory receptors (KIR) are receptors for self-HLA class I molecules, which are expressed on natural killer (NK) cells and small subsets of T-lymphocytes. KIR receptors that do not bind to self-HLA class I have been implicated in the pathogenesis of pure red-cell aplasia and other autoimmune diseases. However, NK cells whose inhibitory receptors lack any apparent self-ligand can also be found in healthy individuals. We therefore tested whether these NK cells are capable of exerting cytotoxic activity against autologous CD34(+) hematopoietic precursors. We detected NK cells whose sole inhibitory receptors were CD94/NKG2-A and that had no affinity for autologous HLA-C molecules. In vitro, such cells were able to kill autologous CD34(+) stem cells that expressed MHC class I antigen at a high level in about 50% of the cases of HLA-C group 2 donors. Two individual clones derived from this NK subpopulation were stimulated by autologous HLA-Cw5/6-positive stem cells, but not by allogeneic HLA-Cw7-positive stem cells. Our findings demonstrate the presence of potentially autoreactive natural killer cells in otherwise healthy individuals.

Chromosome 11 monosomy in conjunction with a mutated SDHD initiation codon in nonfamilial paraganglioma cases

Paragangliomas of the head and neck region are a group of rare, usually benign, slow-growing tumors developing from paraganglionic chemoreceptors in most patients. Mutations in a subunit of the mitochondrial enzyme II complex (succinate dehydrogenase [SDHD]) were shown to be responsible for the formation of paragangliomas. In addition, loss of heterozygosity (LOH) on chromosome 11, mainly in 11q23 (PGL1), was observed recently. We analyzed DNA derived from tumor sections of three unrelated paraganglioma patients (one case with multiple paragangliomas, two cases with single tumors; all of them sporadic cases) for mutations in the SDHD gene by direct sequencing. Microsatellite-based LOH was performed, and events of chromosomal loss were validated by fluorescence in situ hybridization (FISH) on paraffin-embedded tumor and normal tissue by using centromeric satellite DNA. Sequence analysis revealed mutations in SDHD exon 1 in all patients, affecting the initiation codon (M1V). Another alteration was detected in exon 2 but was lacking in tumor DNA and therefore classified as polymorphism (H50R). LOH and FISH analyses demonstrated partial/total monosomy for chromosome 11 in the tumor samples tested. A common genetic mechanism appears to be the pathophysiologic basis for sporadic tumor development because the proposed two-hit model comprising both LOH and point mutation is manifest in our patients. Loss of chromosome 11 regions, including the deletion of PGL1 and PGL2 loci, may result in a more severe phenotype, as exemplified by the development of multiple tumors in one of the patients.

Nonmuscle myosin heavy-chain gene MYH14 is expressed in cochlea and mutated in patients affected by autosomal dominant hearing impairment (DFNA4)

Myosins have been implicated in various motile processes, including organelle translocation, ion-channel gating, and cytoskeleton reorganization. Different members of the myosin superfamily are responsible for syndromic and nonsyndromic hearing impairment in both humans and mice. MYH14 encodes one of the heavy chains of the class II nonmuscle myosins, and it is localized within the autosomal dominant hearing impairment (DFNA4) critical region. After demonstrating that MYH14 is highly expressed in mouse cochlea, we performed a mutational screening in a large series of 300 hearing-impaired patients from Italy, Spain, and Belgium and in a German kindred linked to DFNA4. This study allowed us to identify a nonsense and two missense mutations in large pedigrees, linked to DFNA4, as well as a de novo allele in a sporadic case. Absence of these mutations in healthy individuals was tested in 200 control individuals. These findings clearly demonstrate the role of MYH14 in causing autosomal dominant hearing loss and further confirm the crucial role of the myosin superfamily in auditive functions.

Spiking of Contemporary Human Template DNA with Ancient DNA Extracts Induces Mutations Under PCR and Generates Nonauthentic Mitochondrial Sequences

Proof of authenticity is the greatest challenge in palaeogenetic research, and many safeguards have become standard routine in laboratories specialized on ancient DNA research. Here we describe an as-yet unknown source of artifacts that will require special attention in the future. We show that ancient DNA extracts on their own can have an inhibitory and mutagenic effect under PCR. We have spiked PCR reactions including known human test DNA with 14 selected ancient DNA extracts from human and nonhuman sources. We find that the ancient DNA extracts inhibit the amplification of large fragments to different degrees, suggesting that the usual control against contaminations, i.e., the absence of long amplifiable fragments, is not sufficient. But even more important, we find that the extracts induce mutations in a nonrandom fashion. We have amplified a 148-bp stretch of the mitochondrial HVRI from contemporary human template DNA in spiked PCR reactions. Subsequent analysis of 547 sequences from cloned amplicons revealed that the vast majority (76.97%) differed from the correct sequence by single nucleotide substitutions and/or indels. In total, 34 positions of a 103-bp alignment are affected, and most mutations occur repeatedly in independent PCR amplifications. Several of the induced mutations occur at positions that have previously been detected in studies of ancient hominid sequences, including the Neandertal sequences. Our data imply that PCR-induced mutations are likely to be an intrinsic and general problem of PCR amplifications of ancient templates. Therefore, ancient DNA sequences should be considered with caution, at least as long as the molecular basis for the extract-induced mutations is not understood.

Molecular phylogenetics employing modern and ancient DNA

Comparative studies of DNA in recent populations and characterisation of ancient hereditary material have contributed very interesting facts to our understanding of evolution of modern mankind. Analysis of DNA homology in related species, assessment of mutations and polymorphisms in various populations and new DNA sequence data from prehistoric finds allowed - via sophisticated DNA extraction techniques, PCR, sequencing and digitalised processing of genetic information - insights into possible roots of Homo sapiens and related species, migration patterns and ancient cultural habits, thus enrhing the palaeoanthropological discipline. However, a presentation of this development would not be complete without pointing towards the methodological limitations and manifold presentations burdened with artifacts, data misinterpretation and unjustified conclusions. Presently, this modern field of research is in its consolidation phase and new parameters for quality control and authentication are being implemented to avoid spectacular but unfounded reports. It is expected that most of the problems connected to old biomolecules may be closely related to fossilisation parameters. The future challenge will be the full understanding of the complex and multi-faceted processes underlying diagenesis, including the elucidation of nucleic acid postmortem damage".

A novel CACNA1F mutation in a french family with the incomplete type of X-linked congenital stationary night blindness

PURPOSE

To describe a French family with the incomplete type of X-linked congenital stationary night blindness (CSNB2) associated with a novel mutation in the retina-specific calcium channel alpha(1) subunit gene (CACNA1F).

DESIGN

Interventional case report.

METHODS

Two family members with a history of nonprogressive night blindness and subnormal visual acuity were clinically examined and the genotype determined by molecular genetic analysis.

RESULT

Both patients had clinical manifestations characteristic of CSNB2. Electrophysiologically, we found a predominant reduction of the ERG B-wave in the maximal response. Both rod and cone function were subnormal, with the latter tending to be more attenuated. We identified a C deletion at nucleotide position 4548, resulting in a frameshift with a predicted premature termination at codon 1524.

CONCLUSIONS

The clinical and genetic study of a novel mutation in the CACNA1F gene adds further support to the contention that CSNB2 represents a genetically distinct retinal disorder of a calcium channel.

Isolation of the mouse nyctalopin gene nyx and expression studies in mouse and rat retina

PURPOSE

It has been shown recently that mutations in NYX (nyctalopin on chromosome X), encoding a novel protein associated with the leucine-rich repeat (LRR) protein superfamily, are responsible for the complete form of X-linked congenital stationary night blindness (CSNB1). This study describes the isolation and molecular characterization of the mouse orthologue Nyx and its expression pattern in the retina.

METHODS

Nyx was isolated by conventional DNA library screening and polymerase chain reaction (PCR)-based approaches. Gene expression in different mouse tissues was studied by RT-PCR. Subsequently, the expression pattern of Nyx and its gene product in mouse and rat retinas was investigated by RNA in situ hybridization and immunohistochemistry with Nyx-specific antibodies.

RESULTS

The Nyx gene encodes a protein of 476 amino acids that contain 11 consecutive LRR motifs flanked by amino- and carboxyl-terminal cysteine-rich LRRs. At the amino acid level, Nyx is highly homologous to its human orthologue (86% identity). The gene is expressed in the eye but also, at lower levels, in brain, lung, spleen, and testis. Nyx expression was found during all stages of postnatal retinal development and was confined to cells of the inner nuclear layer and the ganglion cell layer in adult mouse and rat retinas.

CONCLUSIONS

These data suggest an important function of the Nyx protein in the inner retina and provide evidence that CSNB1 is based on a defect in the inner retinal circuitry.

Palaeopathological and variant conditions of the Homo heidelbergensis type specimen (Mauer, Germany)

Although early Homo specimens are now known from a number of African, Asian and European Middle Pleistocene sites, the taxon Homo heidelbergensis was initially introduced for the Mauer jaw recovered in 1907. Fossil hominids from the earlier Middle Pleistocene of Europe are very rare and the Mauer mandible is generally accepted as one of the most ancient, with an age of approximately 700 kyr. A new preparation of the mandible was conducted in 1996 and gave rise to the detailed palaeopathological examination which is presented here. Based on comparative analyses, the extreme breadth of the mandibular ramus and its flat intercondylar incision, in conjunction with the flattening and broadening of the coronoid process tip, results either from an idiosyncratic pattern of the course and insertion of the temporalis muscle on the coronoid process or from the temporalis possessing an accessory head. The incidence of periodontal pocketing, together with a vertical reduction of the alveolar margin to approximately 3.00 mm, and a slight protuberance formed in vicinity of the right M(2)can safely be interpreted as pathognomonic indications of periodontal disease. The short distance between the enamel-dentine junction of the teeth and the horizontal alveolar margins could either be an inherited variant or may result from incipient osteoporosis. In addition, an arthrotic condition with slight osteophytic peripheral exostoses and an arthrolit (i.e. an articular calculus or "joint mouse") on the left condylus articularisand a depression in the medial part of the left mandibular condyle extending into the inferior part of the ramus are present. These features are indicative of a trauma-induced osteochondrosis dissecans. The diagnosis therefore suggests that the observed depression results from a well-healed fracture. This traumatic event illustrates the demanding living conditions endured by humans during the European Middle Pleistocene. The variations and pathological conditions observed in Mauer do not question the mandible's role as type specimen for the taxon Homo heidelbergensis.

Uncommon cytidine-homopolymer dimorphism in 5'-UTR of the human otoferlin gene

Human otoferlin, homologous to the Caenorhabditis elegans spermatogenesis factor FER-1 that was shown to be involved in membrane vesicle fusion, belongs to a group of membrane-anchored cytosolic proteins and is found expressed in brain, cochlear inner hair cells and vestibular type I sensory cells. Nonsense and missense mutations of OTOF lead to an autosomal recessive deafness phenotype (DFNB9). We describe here an unusual C-homopolymer dimorphism at position -136 of 5'-UTR of the OTOF short splice form. Although at first identified within a family with a hereditary component of hearing deficiency this C3/C5 dimorphism is found frequently in European populations (0.4 for C3, 0.6 for C5) and does not segregate with the deafness phenotype. The polymorphic site may become useful for studying the origin of different OTOF mutations within various populations, for assessing recombination events within large pedigrees as well as founder effects and for association studies in further deafness phenotypes.

Ten novel ORF15 mutations confirm mutational hot spot in the RPGR gene in European patients with X-linked retinitis pigmentosa

RGPR was the first gene found to be mutated in XLRP, the subtype of RP displaying the most severe form of retinal degeneration with partial or complete blindness in the third or fourth decade of life. Despite the RP3 locus on Xp21.1 accounting for 60-90% of XLRP, only 10-20% of identified RPGR mutations were reported in earlier analyses. This discrepancy appeared to be resolved when Vervoort et al. identified a mutational hot spot in a new purine-rich 3' exon (ORF15) that accounted for 60% of their XLRP patients [Vervoort et al., 2000]. In our mutation screening of 37 unrelated European XLRP patients we identified two recently described deletions and 10 novel mutations in exon ORF15 of RPGR, 4 of which were nonsense and 6 frameshift mutations. The latter included one duplication and 5 deletion mutations, all of which lead to a downstream premature termination. No mutations were detected in the additionally screened new exon ORF14. The data reported here, together with previous findings, document a significant clustering of mutations as well as polymorphisms in ORF15 of RPGR. In our unselected XLRP patient population, ORF15 mutations constitute 32% of cases, a finding that contradicts the results of Vervoort and coworkers [Vervoort et al., 2000] but is in agreement with a more recent study on North American XLRP patients [Breuer et al., 2002]. The observed prevalence is sufficient to justify an initial mutation screening of ORF15 in the genetically heterogeneous group of XLRP.

Documenting ancient DNA quality via alpha satellite amplification and assessment of clone sequence diversity

C/G-->T/A nucleotide alterations have been shown to hamper the straightforward interpretation of mitochondrial DNA sequence data derived from ancient tissues. Attempting to characterise this finding with respect to nuclear DNA, we contrasted two established protocols: (i) an enzymatic repair of damaged DNA, thereby translating and closing nicks in the DNA, and (ii) the application of N-phenacylthiazolium bromide, which cleaves glucose-derived protein crosslinks, presumably derived from Maillard reactions. We used medieval human bones that were refractory to standard PCR procedures. Due to negligible presence of short tandem repeat loci and also mitochondrial sequences, the extracted ancient DNA needed a higher copy PCR system to yield amplification products. The chosen PCR target was specific alphoid repetitive DNA with an experimentally determined minimum of 1000 copies per haploid genome. Alphoid repeat segments were generated from both contemporary DNA and DNA extracts of two human skeletons dating from 450-600 AD (omitting uracil N-glycosylase pre-treatment of the extracted samples), and were subsequently cloned and sequenced. The sequences were evaluated for the number and type of nucleotide alterations noted after the different pre-treatments, and were compared to our alphoid consensus sequence generated from modern DNA. Both methods failed to reflect the expected 32% variability among single alphoid repeats (accounting for locus-specific differences and polymerase errors) as well as to display the actual 2.88 ratio of transitions to transversions. Our data obtained from high-copy-number nuclear DNA mirror the phenomenon of sequence deviations observed in mitochondrial DNA extracted from old specimens.

Phenotypic expression of the complete type of X-linked congenital stationary night blindness in patients with different mutations in the NYX gene

PURPOSE

To describe the clinical phenotype of the complete type of X-linked congenital stationary night blindness (CSNB1) with different types of mutations in the NYX gene.

METHODS

The clinical and genetic data from 18 male patients with eight different mutations from two ophthalmological institutes were reviewed. The variability in refractive error, reduced visual acuity and full-field electroretinogram (ERG) recordings was examined.

RESULTS

Parameters were quantitatively analyzed based on the classification of mutations according to their predicted effect on protein structure and function. CSNB1 patients with mutations changing structurally conserved residues ( n=12) tended to have a lower degree of myopia than patients with mutations of non-conserved residues ( n=6). Visual acuity loss and the 30 Hz flicker ERG recordings were similar in the two groups. Values for the b/a amplitude ratio tended to be clustered in patients carrying the same mutation. Refractive error and the b/a amplitude ratio were highly correlated between the two eyes of an individual.

CONCLUSIONS

These data suggest correlations between phenotypic expression in CSNB1 and individual genotypes as well as class types of mutations based on the extent of structural amino acid conservation. A high inter-eye correlation suggests that other genetic or environmental factors, rather than chance, play a part in determining the phenotypic diversity in CSNB1.

Hirschsprung, RET-SOX and beyond: the challenge of examining non-mendelian traits (Review)

Hirschsprung disease (HSCR), or congenital intestinal aganglionosis, is a common hereditary disorder causing intestinal obstruction, thereby showing considerable phenotypic variation in conjunction with complex inheritance. Moreover, phenotypic assessment of the disease has been complicated since a subset of the observed mutations is also associated with several additional syndromic anomalies. Coding sequence mutations in e.g. RET, GDNF, EDNRB, EDN3, and SOX10 lead to long-segment (L-HSCR) as well as syndromic HSCR but fail to explain the transmission of the much more common short-segment form (S-HSCR). Furthermore, mutations in the RET gene are responsible for approximately half of the familial and some sporadic cases, strongly suggesting, on the one hand, the importance of non-coding variations and, on the other hand, that additional genes involved in the development of the enteric nervous system still await their discovery. For almost all of the identified HSCR genes incomplete penetrance of the HSCR phenotype has been reported, probably due to modifier loci. Therefore, HSCR has become a model for a complex oligo-/polygenic disorder in which the relationship between different genes creating a non-mendelian inheritance pattern still remains to be elucidated.

Thirty distinct CACNA1F mutations in 33 families with incomplete type of XLCSNB and Cacna1f expression profiling in mouse retina

X-linked CSNB patients may exhibit myopia, nystagmus, strabismus and ERG abnormalities of the Schubert-Bornschein type. We recently identified the retina-specific L-type calcium channel alpha1 subunit gene CACNA1F localised to the Xp11.23 region, which is mutated in families showing the incomplete type (CSNB2). Here, we report comprehensive mutation analyses in the 48 CACNA1F exons in 36 families, most of them from Germany. All families were initially diagnosed as having the incomplete type of CSNB, except for two which have been designated as Aland Island eye disease (AIED)-like. Out of 33 families, a total of 30 different mutations were identified, of which 24 appear to be unique for the German population. The mutations, 20 of which are published here for the first time, were found to be equally distributed over the entire gene sequence. No mutation could be found in a classic AIED family previously shown to map to the CSNB2 interval. Cacna1f expression in photoreceptor-negative mice strains indicate that the gene is expressed in the outer nuclear, the inner nuclear, and the ganglion cell layer. Such a distribution points to the central role of calcium regulation in the interaction of retinal cells that mediate signal transmission.

Substitutions in the conserved C2C domain of otoferlin cause DFNB9, a form of nonsyndromic autosomal recessive deafness

DFNB, the nonsyndromic hearing loss with an autosomal recessive mode of inheritance constitutes the majority of severe to profound prelingual forms of hearing impairment, usually leading to inability of speech acquisition. We analyzed a consanguineous family with autosomal recessive deafness which has been shown to segregate within chromosomal region 2p23.1 (DFNB9; MIM 601071). By SSCP analysis and DNA sequencing of the 48 exons of the DFNB9 gene, coding for otoferlin, previously reported mutations in OTOF were excluded. Next to a frequent T > C single nucleotide polymorphism in exon 8, two novel mutations linked in exon 15 of the OTOF long splice form were identified comprising substitutions at positions 490 (Pro > Gln) and 515 (Ile > Thr), both located in the conserved Ca(2+) binding C2C domain of this peptide. Comparisons of homology using human and mice otoferlins and closely related peptides and computer simulation analyses suggest that changes in the mutated segment's secondary structure affect the Ca(2+) binding capacity of the C2C domain in otoferlin.

Detection of bone glue treatment as a major source of contamination in ancient DNA analyses

Paleogenetic investigations of ancient DNA extracted from fossil material is for many reasons susceptible to falsification by the presence of more recent contamination from several sources. Gelatine-based bone glue that has been used extensively for nearly two centuries by curators to preserve hard tissues contributes nonauthentic DNA to paleontological material. This fact has been frequently neglected and is barely mentioned in the literature. Now paleogeneticists, curators, and conservators are faced with the problem that treatment of samples with adhesives and consolidants for conservatory purposes has seldom been recorded. Here, we show that racemization of amino acids, and in particular serine, is an excellent indicator for the treatment of paleontological samples with glue.

[Classification of a 300,000-year-old dental crown of the upper loamy deposit of the Bad Canstatter travertine zone]

Hominid dental remains were recovered in association with fossil bones and artifacts during systematic excavations in a loamy deposit located between the two travertine zones T4 and T5 at Stuttgart-Bad Cannstatt, Southwest Germany. Direct dating of a hominid tooth crown with thermoluminescence resulted in a date of 300 kya, which is in agreement with the Holstein Interglacial floral and faunal composition of this layer. The specimen is a lower left canine with hypoplastic morphology. This interpretation is supported by thorough assessment of its overall morphology, comparative metric evaluation, and by scanning electron microscopy analyses of the enamel prisms. Additional microstructural comparison of these dental remains with a tooth from the same site, but derived from a Cervidae specimen supported the distinct differences between both teeth. Here we discuss both the classification and significance of the specimen's evolutionary position as well as compare this specimen with stomatologic results from previous palaeopathological research.