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Nager syndrome belongs to the group of acrofacial dysostosis, which are characterized by the association of craniofacial and limb malformations. Recently, exome sequencing studies identified the SF3B4 gene as the cause of this condition in most patients. SF3B4 encodes a highly conserved protein implicated in mRNA splicing and bone morphogenic protein (BMP) signaling. We performed SF3B4 sequencing in 14 families (18 patients) whose features were suggestive of Nager syndrome and found nine mutations predicted to result in loss-of-function. SF3B4 is the major gene responsible for autosomal dominant Nager syndrome. All mutations reported predict null alleles, therefore precluding genotype-phenotype correlations. Most mutation-negative patients were phenotypically indistinguishable from patients with mutations, suggesting genetic heterogeneity.

Split hand/foot malformation (SHFM) with long-bone deficiency (SHFLD, MIM#119100) is a rare condition characterized by SHFM associated with long-bone malformation usually involving the tibia. Previous published data reported several unrelated patients with 17p13.3 duplication and SHFLD. Recently, the minimal critical region had been reduced, suggesting that BHLHA9 copy number gains are associated with this limb defect. Here, we report on 13 new families presenting with ectrodactyly and harboring a BHLHA9 duplication.

Review on MUC4 (mucin 4, cell surface associated), with data on DNA, on the protein encoded, and where the gene is implicated.

Human respiratory mucins are secreted by goblet cells and mucous glands of the respiratory mucosa. They consist of a broad family of complex glycoproteins with different peptides, or apomucins, corresponding to several genes located on at least three different chromosomes. Glycosylation, the major posttranslational phenomenon, is responsible for about 70-80% of the weight of mucins: it produces an extraordinary diversity of O-glycosidically linked carbohydrate chains which are expressed as several hundreds of different chains in the mucins of a single individual. The variety of mucin peptides and the diversity of carbohydrate chains probably allows many interactions, especially with microorganisms: this may be an essential factor in the defence of the underlying respiratory mucosa.

Calcium is a major ion in human metabolism and its level is highly controlled. This regulation is performed via the Calcium Sensing Receptor, a discovery which ten years ago led to the explanation of a number of clinical disorders. The syndromes caused by CaSR abnormalities are characterized by hypercalcemia or hypocalcemia, associated with inappropriate calciuria. An underlying genetic or auto-immune cause may be demonstrated. High blood calcium levels linked to mutations of the CaSR gene lead to familial hypocalciuric hypercalcemia and the neonatal and non neonatal forms with severe hypercalcemic. Hypocalcemia determined by mutations in the CaSR gene include autosomal dominant hypocalcemia and its sporadic form. Another clinical presentation similar to Bartter syndrome has been reported. Auto-antibodies directed against CaSRs, seen in auto-immune diseases, can lead to similar clinical presentations. Finally, CaSR polymorphisms modulate the range of blood calcium levels. With diagnosis of these diseases deleterious therapeutics can be avoided. The discovery of this receptor has led to new therapeutic prospects such as calcimimetics for hyperthyroidism.

Between 1971 and 2002, 80 patients underwent surgery for insulinoma at the Department of General and Endocrine Surgery of the Lille University Hospitals. The present report deals with 13 patients with proven multiple endocrine neoplasia type I (MEN I) or supposed genetic-related insulinomas. This entity differs from spontaneous insulinoma by the presence of multiple foci in the pancreas. Enucleation is not advised in this setting due to the strong likelihood of persistence or recurrence. Various studies suggest different strategies for preoperative localization and surgical approach. We analyzed retrospectively the surgical strategy proposed by the A.F.C.E. and G.E.N.E.M. The purpose of this study was to validate the strategy, integrate the contribution of genotypic diagnosis, simplify preoperative imaging studies, and re-evaluate the value of intraoperative baseline secretin-stimulated insulin measurements. We recommend preoperative endoscopic ultrasonography of the pancreatic head only and routine left pancreatectomy with enucleation of cephalic tumors under intraoperative hormone monitoring. Preoperative invasive localization studies are proposed only if the endoscopic ultrasonography is negative for the pancreatic head. Intraoperative secretin stimulation test can be useful in difficult cases, especially with concurrent nesidioblastosis or in case of secondary surgery. All but one of the 13 patients achieved long-term cure with this strategy.

To define a clinical and secretory profile of paragangliomas extra-adrenal chromaffin tumors.From 1971 throughout 2002, 39 paragangliomas have been observed in 38 patients (22 male, 16 female, average age 41,2 years).Four were located above the diaphragm, 35 were sub-phrenic (6 of the organ of Zuckerkandl), 32 secreted catecholamines, 23 were hypertensive (with only one without hypersecretion of catecholamines). Among 29 (131)I-metaiodobenzylguanidine scans (MIBG) reviewed, 20 tumors took up the radiopharmaceutical. The treatment was surgical in 35 cases with addition of external radiotherapy and MIBG in one case each; two patients died before any treatment. Two patients with persistent disease after surgery were successfully treated by surgery or MIBG. Histologically, 20 were malignant and 17 were seemingly benign. All exclusive dopamine secreting paragangliomas were malignant. Six patients relapsed two of which for a tumor initially classified as benign. The treatment of recurrences was surgical, by MIBG or by external radiotherapy. Nine patients had a family history of chromaffin tumor(s). The genetic survey made in five of these nine patients was positive in all cases.

Multiple endocrine neoplasias (MEN) are autosomal dominant inherited syndromes characterized by the association of different glandular lesions in several members of the same kindred. The main clinical features of MEN 1 include primary hyperparathyroidism, pancreatic islet cell tumors and pituitary adenomas; less common features are adrenal adenomas, thymic and bronchial carcinoid tumors, lipomas and various cutaneous lesions. The MEN 2 syndromes (MEN 2A, MEN 2B and familial medullary thyroid carcinomas) are characterized by high penetrance of medullary thyroid carcinoma and differ in their variable expression of pheochromocytoma, hyperparathyroidism and other clinical features.MEN 1 tumor suppressor gene encodes a nuclear protein, menin, which interacts with different regulation transcription factors. The MEN 2 syndromes are caused by germ-line mutations of the RET proto-oncogene, which encodes a transmembrane tyrosine kinase. Genetic testing for mutations in these 2 genes allows identification of individuals predisposed to the disease, early diagnosis, and clinical and therapeutic management.Fundamental approach will allow a best comprehension of physiopathogenic mechanisms of these disorders and the improvement of therapeutic management.

Human mucins are large O-glycoproteins expressed by epithelial cells. Mucins are thought to be implicated in cell protection, cell adhesion and signalling. The aim of this study was to investigate the expression of the human mucin genes (MUC1-4, 5AC, 5B, 6-7) in normal kidney and renal cell carcinoma.We analysed by in-situ hybridization, immunohistochemistry and reverse transcriptase-polymerase chain reaction (RT-PCR) the expression of these genes in normal adult kidney (n=14) and renal cell carcinomas (n=29). MUC1, MUC3 and MUC6 were expressed both in normal kidney and in renal carcinomas. In normal kidney, MUC1 was expressed in the distal convoluted tubules and in collecting ducts, whereas MUC3 was restricted to the proximal tubules. MUC4 was strongly expressed in epithelial urothelial cells of pyelocalyceal cavities. MUC6 was only detected by RT-PCR. In renal carcinoma, we showed a heterogeneous expression of MUC1 and MUC3 with an over-expression of MUC3 in renal clear cell carcinoma. The level of MUC3 expression by in-situ hybridization was associated with the nuclear grade in clear cell carcinoma.This study is the first large series investigating human mucin gene expression in the kidney. MUC1, MUC3 and MUC6 are expressed in normal and tumour kidney. The over-expression of MUC3 in renal cell carcinomas favours its implication in renal tumorigenesis.

Alpha1-antitrypsin (alpha1AT) deficiency is an autosomal recessive disorder that can cause pulmonary emphysema and liver disease. We report here the case of a 59-year-old woman who was admitted to hospital for evaluation of jaundice. She had no history of hepatitis or childhood liver disease. She had never received a blood transfusion, nor had she abused drugs or alcohol. Transjugular liver biopsy was then performed and revealed a micronodular cirrhosis. Ten months later, because of persistent liver cell failure and ascites, she underwent an orthotopic liver transplantation. Investigation of alpha1AT system in the proband revealed a substantial decrease in serum alpha1AT associated with a low elastase inhibitory capacity. The Pi phenotype revealed a PiM-like profile. Sequencing of exons 1-5 demonstrated the presence of the M3 allele. Moreover, a triple nucleotide deletion was detected in exon 2 of one allele. This caused an "in-phase" frameshift, coding for a protein deficient in a single Phe residue, which corresponded to the Mmalton variant. After liver biopsy, periodic acid-Schiff-positive acidophilic bodies resistant to diastase digestion were observed in the cytoplasm of hepatocytes. These results demonstrated that our patient had a heterozygous M3Mmalton alpha1AT genotype related to a deficiency phenotype. This observation is the first of a patient with heterozygous Mmalton genotype associated with an alpha1AT deficiency that induced severe liver disease requiring orthotopic liver transplantation.

The human mucin gene MUC4 encodes a large transmembrane mucin that is thought to play important roles in tumor cell biology and that is overexpressed in human pancreatic carcinomas. In this report, we describe the structure and functional activity of the 5'-flanking region, including 1.0 kilobase of the promoter. The long 5'-untranslated region (2.7 kilobases) is characterized by a high content of GC in its 3'-end. The first TATA box was located at -2672/-2668. Multiple transcription start sites and a high density of putative binding sites for Sp1 (GC and CACCC boxes), AP-1/-2/-4, cAMP-responsive element-binding protein, GATA, GR, and STAT transcription factors were found within the 5'-flanking region. Transcriptional activity of the promoter was assessed using pGL3-luciferase deletion mutants in two MUC4-expressing (CAPAN-1 and CAPAN-2) and one nonexpressing (PANC-1) pancreatic cancer cell line. Two highly active fragments (-219/-1 and -2781/-2572) that drive MUC4 transcription in CAPAN-1 and CAPAN-2 cells were identified. Gel retardation assays indicated that Sp1 and Sp3 bind to cognate cis-elements found in the 5'-flanking region and that Sp1 transactivates, whereas Sp3 inhibits the GC-rich region (-464/-1) in CAPAN-2 cells. Activation of protein kinase C with phorbol ester and treatment of cells with epidermal growth factor and transforming growth factor-alpha resulted in up-regulation of the promoter. Tumor necrosis factor-alpha and interferon (IFN)-gamma inflammatory cytokines had no or mild effect on MUC4 transcriptional activity when used alone. However, a very strong synergistic effect (10-12-fold activation) between IFN-gamma and tumor necrosis factor-alpha or IFN-gamma and transforming growth factor-alpha was obtained in CAPAN-2 cells. Altogether these results demonstrate that the 5'-flanking region of MUC4 contains epithelial cell-specific, positive, and negative regulatory cis-elements, that Sp1/Sp3 are important regulators of MUC4 basal expression, and that its regulation in pancreatic cancer cells involves complex interplay between several signaling pathways.

In gastric cancer, altered expression of MUC1, MUC2, MUC5AC, and MUC6 mucin genes has already been described. We show in this report by the means of in situ hybridization, reverse transcriptase-polymerase chain reaction, and transfection assays that MUC5B is also abnormally expressed in gastric carcinomatous tissues and cell lines. We thus undertook to elucidate the molecular mechanisms that regulate the transcription of MUC5B in gastric cancer cells. To this end, high expressing (KATO-III) and low expressing (AGS) gastric cancer cell lines were chosen to study human mucin gene MUC5B expression and promoter activity. Sequencing of the promoter region revealed a distal TATA box located 1 kilobase upstream of the proximal TATA box. Functional activity of the promoter was addressed by using deletion mutants covering 2044 nucleotides upstream of the MUC5B transcription start site. We identified a distal promoter 10 times more active than the proximal promoter in KATO-III cells. In AGS cells, both promoters, much less active, showed the same range of activity. Binding assays allowed us to show that the transcription factor ATF-1 binds to a cis-element present in the distal promoter. Sp1, which binds to both promoters specifically transactivates the proximal promoter. Treatment of transfected cells with PMA, cholera toxin A subunit, and calcium ionophore showed that only PMA led to a substantial activation of the distal promoter. MUC5B 5'-flanking region having a high GC content, influence of methylation on the MUC5B expression was assessed. Our results indicate that repression of MUC5B expression visualized in AGS cells is due in part to the presence of numerous methylated cytosine residues throughout the 5'-flanking region. Altogether these results demonstrate that MUC5B expression in gastric cancer cells is governed by a highly active distal promoter that is up-regulated by protein kinase C and that repression is under the influence of methylation.

Mucinous tumours of the ovary are characterized by mucin-secreting cells exhibiting a variable endocervical, intestinal, gastric or pancreatobiliary phenotype as ascertained by microscopy, electron microscopy, histochemistry or immunohistochemistry. The molecular mechanisms underlying the tumourigenesis process are not well understood. The mucin glycoproteins expressed by ovarian mucinous tumours have not been fully characterized, but mucins are known to be implicated in tumour progression in various epithelial neoplasms. The purpose of this study was to evaluate the expression of mucin genes (MUC1, MUC2, MUC3, MUC4, MUC5AC, MUC5B, MUC6) in ovarian mucinous tumour cells, to relate MUC gene expression to the histological diagnosis, and to compare the expression patterns with those observed in normal tissues. The expression of mucin genes was evaluated by in situ hybridization in 21 mucinous tumours (11 adenomas and ten borderline tumours). Heterogeneity of expression correlated with morphological heterogeneity. Intense expression of the MUC5AC gene, suggesting a gastric surface cell phenotype, was demonstrated in 18/21 tumours (86%). Goblet cells expressing the MUC2 gene and columnar cells expressing the MUC3 gene were consistent with an intestinal phenotype, which was observed in 15 tumours (71%) including nine adenomas and six borderline tumours. Major expression of MUC4 and MUC5B consistent with an endocervical phenotype was observed in seven benign (64%) and three borderline (30%) tumours. In all, the MUC profiles suggested gastrointestinal-type cells in 13 cases (62%), gastric-type cells in five cases (24%), and intestinal-type cells in two cases (one benign, one borderline) (9%); the results were inconclusive in one borderline tumour (5%). It is concluded that gastric and, to a lesser degree, intestinal differentiation are early and almost constant events in ovarian mucinous tumourigenesis.

Esophageal carcinoma includes squamous cell carcinoma and Barrett's adenocarcinoma. The latter usually develops from a premalignant lesion named Barrett's esophagus. MUC genes are known to be specifically expressed in the normal, premalignant and malignant epithelia of various tissues. The aim of this study was to establish the pattern of MUC gene expression in the esophageal mucosa under normal conditions, and under pathological conditions such as squamous cell carcinoma, Barrett's esophagus and adenocarcinoma. Samples of esophageal control mucosa, metaplastic and malignant tissues were obtained from 40 patients undergoing esophagectomy for squamous cell carcinoma (n = 17), or Barrett's esophagus with adenocarcinoma (n = 23). In situ hybridization and northern blot were used with probes specific for the MUC1, MUC2, MUC3, MUC4, MUC5AC, MUC5B, MUC6 and MUC7 genes to assess their expression in these samples. Submucosal glands of control esophageal mucosa expressed MUC5B, whereas MUC1 and MUC4 were found in both control epithelium and squamous cell carcinoma. MUC4 expression correlated with squamous cell differentiation. Barrett's adenocarcinoma exhibited various patterns of MUC gene expression, the strongest being in the well-differentiated mucinous adenocarcinomas. Barrett's metaplasia was also associated with a specific MUC gene expression pattern, since the gastric apomucin mRNAs, MUC5AC and MUC6, were expressed in gastric metaplasia, and the intestinal apomucin mRNAs, MUC3, MUC4 and mostly MUC2, in intestinal metaplasia. Residual expression of gastric apomucin mRNAs was found in intestinal metaplasia. From these results, we conclude that MUC genes can be considered reliable phenotypic markers of the esophageal cell differentiation, thus providing new insight into the development of Barrett's esophagus.

The MUC4 mucin gene encodes a putative membrane-anchored mucin with predicted size of 930 kDa, for its 26.5-kb allele. It is composed of two regions, the 850-kDa mucin-type subunit MUC4alpha and the 80-kDa membrane-associated subunit MUC4beta. In this study, we cloned and characterized unique MUC4 cDNA sequences that differ from the originally published sequence. Eight alternative splice events located downstream of the central large tandem repeat array generated eight new, distinct cDNAs. The deduced sequences of these MUC4 cDNAs (sv1-MUC4 to sv8-MUC4, the full length cDNA being called sv0-MUC4) provided seven distinct variants, five secreted forms and two membrane-associated forms. Furthermore, two other alternative splicing events located on both sides of the tandem repeat array created two variants, MUC4/Y and MUC4/X, both lacking the central tandem repeat. Therefore, MUC4 can be expressed in three distinct forms, one membrane-bound, one secreted, and one lacking the hallmark feature of mucin, the tandem repeat array. Although no specific function has yet been discovered for the family of proteins putatively produced from the unique MUC4 gene, we suspect that the MUC4 proteins may be implicated in the integrity and renewal of the epithelium.

Mucous cells in the respiratory tract contribute to the maintenance of the normal epithelial cell population via mechanisms of cell proliferation and differentiation. Mucous cell hyperplasia often occurs as a basic response to injury in the tracheobronchial epithelium. These cells are also thought to be involved in the histogenesis of epidermoid metaplasia. A typical biochemical feature of these cells is mucus secretion. Aberrant glycosylation or under-glycosylation of mucins is well known in cancer; however, the specific role played by mucin genes is at present unclear. To provide information regarding the expression of these genes in squamous metaplasia and squamous cell carcinoma, we analyzed and compared the expression of MUC1-MUC7 genes by in situ hybridization in control respiratory mucosa and lesions associated with neoplasia (hyperplasia, metaplasia and dysplasia) and squamous cell carcinomas. MUC4 was expressed independently of mucus secretion since it was expressed weakly by basal cells and probably by ciliated cells as well as collecting ducts, epidermoid metaplasia with complete squamous cell differentiation, and most of epidermoid carcinomas even well differentiated and keratinized. In squamous metaplasia and dysplasia, MUC4 gene expression was diffuse and less intense than in normal epithelium. MUC5AC was overexpressed in dysplasia as well as in mucous cell and basal cell hyperplasia and undetectable when squamous differentiation was achieved.

Familial medullary thyroid carcinoma (FMTC) and multiple endocrine neoplasia type 2A syndromes are dominantly inherited diseases caused by activating germline mutations of the RET protooncogene. The majority of these patients carry a germline point mutation affecting one of five cysteine residues encoded by exon 10 (codon 609, 611, 618, or 620) or 11 (codon 634). In a few FMTC families, point mutations involving noncysteine codons in exon 13 (codons 768, 790, and 791), 14 (codon 804), or 15 (codon 891) have been reported. Hirschsprung's disease is a nonneoplastic disorder associated with RET mutations leading to a loss of function effect. Mutations are identified in 50% of the familial cases and are scattered along the gene. We now report the study of a FMTC family with four affected members and a history of fatal neonatal intestinal obstruction in the sister of the proband. Genetic analysis demonstrated the absence of an usual FMTC mutation and the presence of a germline 9-bp duplication in RET exon 8 in the heterozygous state in all patients with MTC. This new mutation creates an additional cysteine residue in the extracellular cysteine-rich domain of RET. Further studies are warranted to confirm whether this new mutation is causing MTC only or could be associated with Hirschsprung's disease.

Multiple Endocrine Neoplasia type 1 (MEN1, OMIM 131100, Wermer syndrome) is characterized by inherited predisposition to primary hyperparathyroidism, endocrine pancreatic-duodenal, pituitary, adrenal glands tumors and benign and/or malignant proliferations of diffuse neuroendocrine tumors in thymus and bronchi, formerly defined as carcinoid tumors. Minor lesions have been observed in MEN1 patients such as cutaneous tumors (angiofibroma, lipoma, lentiginosis), thyroid epithelioma and tumors of the central nervous system, mainly spinal ependymoma. The MEN1 gene, a locus encompassing a 9 kb of genomic sequence contains 10 exons, the first exon being untranslated. The protein encoded by this gene was called menin and has been shown to contain two nuclear localization signals (NLS), suggesting a major function in the nucleus. Germline MEN1 mutations have been described in more than 150 families and are spread throughout the entire coding sequence. More than 70% of the mutations alter one or both NLS and no genotype-phenotype correlations were found to date. The MEN1 gene seems to be involved in a 20-30% of sporadic parathyroid and pancreatic/bronchic neuroendocrine tumors, but less than 1% of pituitary sporadic tumors. Further knowledge on the intracellular function of menin will be needed to understand the pathogenic effect of truncating and missense mutations of this gene in the initiation of endocrine cells tumorigenesis.

Occurrence of mucinous tumors is favored by Peutz-Jeghers syndrome (PJS). A case of bilateral ovarian mucinous tumor associated with ovarian mature teratoma occurring in a 22-year-old woman with PJS was reported. Tumor cells included 5 cell types: tall columnar mucinous pale cells with neutral mucins; goblet cells with acidic nonsulfated mucins; non mucinous columnar cells; mucinous cuboidal cells lining small glands; endocrine cells. Expression of the MUC2, MUC3, MUC5AC and MUC6 genes was demonstrated by in situ hybridization according to cell type. Some atypia and numerous mitotic figures were observed in basal glands. Diagnosis was ovarian borderline mucinous tumor with gastric and intestinal phenotype associated with PJS.

International audience; The complete structure of the DNA encoding the polypeptide chain of human mucin MUC5B has been determined. In this paper, we report the full-length cDNA (3886 bp) and genomic (15,143 bp) sequences upstream of the unusually large central exon of the human mucin gene MUC5B. This region, composed of 29 exons, encodes 1283 amino acid residues. Exon sizes vary from 44 to 262 bp, and intron sizes range from 87 to 1703 bp. We determined the 5'-end of MUC5B by performing rapid amplification of cDNA ends-polymerase chain reaction experiments leading to the same length of the amplified product and by using primer extension experiments. A putative translation start site was found at nucleotide +37. We compared the amino-terminal region of MUC5B with those of pro-von Willebrand Factor, MUC2 and MUC5AC, and animal mucins, RMuc2, PSM, and FIM-B.1. The primary amino acid sequence with a high content of cysteine residues demonstrates a high degree of similarity with other members of the 11p15 mucin gene family, particularly MUC5AC. The complete genomic organization and both full-length genomic and cDNA sequences of MUC5B have been elucidated. This gene contains 48 exons and encodes 5662 amino acid residues to give a polypeptide with a Mr approximately 600,000.

Of the nine mucin genes that have been characterized, only MUC1 and MUC7 have been fully sequenced, and their transcripts can be detected as distinct bands of predicted size by Northern blot analysis. In contrast, the RNA patterns observed for each of the other MUC genes have usually shown a very high degree of polydispersity. This polydispersity has been believed to be one of the typical features of the mucin mRNAs, but until now, its origin has remained unexplained. In the work described in the present paper, we investigated two possible kinds of explanation for this phenomenon: namely that the extensive polydispersity results from a biological mechanism or that it is artifactual in origin. The data obtained, as a result of improving the purification and blotting methods, allowed us to show that in all of the tissues analyzed, each of the genes, MUC2-6, expresses mRNAs that are stable and are of an unusually large size to be found in eukaryotes (14-24 kilobases). Moreover, allelic variations in length of these mucin transcripts were observed. We demonstrate that these variations are directly related to the variable number of tandem repeat polymorphisms seen at the DNA level.

The article must therefore be hereby marked “advertisement” in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.; International audience; Human mucin gene MUC5B is mapped clustered with MUC6, MUC2, and MUC5AC on chromosome 11p15.5. We report here the isolation of three overlapping genomic clones of human MUC5B spanning approximately 40 kilobases. We have determined their partial restriction maps and the intron-exon boundaries of the central region encoding a single open reading frame. This coding region has been completely sequenced. Its length is 10,713 base pairs, and it encodes a 3570-amino acid peptide. Nineteen subdomains have been individualized. Some subdomains show similarity to each other, creating larger composite repeat units that we have called super-repeats. Four super-repeats of 528 amino acid residues are thus observed within the central exon. Each comprises (i) a subdomain composed of 11 repeats of the irregular repeat of 29 amino acid residues, (ii) a unique conserved subdomain with no typical repeat, and (iii) a cysteine-rich subdomain. This latter subdomain has high sequence similarity to the cysteine-rich domains described in MUC2 and MUC5AC. Sequence data of these three genes, together with their clustered organization, lead us to suggest that they may be a part of a multigene family. The super-repeat present in MUC5B is the largest ever determined in mucin genes and the central exon of this gene is, by far, the largest reported for a vertebrate gene.

The use of a probe (JER64) containing a mucin 4 (MUC4) cDNA insert of 1.83 kb allowed to assign by in situ hybridization, the MUC4 gene to 3q29. This probe detected RFLPs with all restriction enzymes used (BamHI, HindIII, PstI, EcoRI, and TaqI). Particularly numerous alleles were observed with PstI, EcoRI and TaqI, in a small sample of unrelated DNAs (25 digested with PstI, 8 with EcoRI and 8 with TaqI). The PIC values were 0.69, 0.63 and 0.70 for PstI, EcoRI and TaqI respectively. The polymorphisms observed of variable number of tandem repeat (VNTR) type are in relation with the presence of tandemly repeated nucleotide sequences in MUC4 gene.

Pulmonary maturity of the fetus can be evaluated by the lecithin/sphingo-myelin (L/S) ratio in amniotic fluid. To existing methods of lipid extraction, precipitation with acetone and chromatography, we add a simple and accurate estimation of sphingomyelins (S) and precipitated lecithins (Lp) without acid digestion. The method is reproducible (C.V.

Pulmonary maturity of the fetus can be evaluated by the lecithin/sphingomyelin (L/S) ratio in amniotic fluid. To existing methods of lipid extraction, precipitation with acetone and chromatography, we add a simple and accurate estimation of sphingomyelins (S) and precipitated lecithins (Lp) without acid digestion. The method is reproducible (C.V. less than 9%) for the measurement of Lp/S ratio and gives with accuracy the concentrations of Lp, avoiding possible errors in interpretation of Lp/S. Our results show that at 35 weeks of normal gestation, Lp/S ratio is about 2 and Lp concentration, 10 mg/1.

Hydrolysis of a solution of amylopectin by serum or urinary amylase leads to a reduction of the turbidity of this solution, observed at 340 nm. Adapted to centrifugal analysis, this method permits 15 estimations in 3 minutes with a serial reproducibility of 2.7 per cent, and a daily reproducibility of 6 per cent. The correlation with a nephelemetric method of estimation gives r = 0,969, with an enzyme method r = 0,957 and with an amyloclastic method, r = 0,919.

We describe a new specific method for measuring lecithin, sphingomyelin, and phosphatidylglycerol in amniotic fluid by thin-layer chromatography, with use of a hydrogen flame ionization detector. After extraction and acetone precipitation to isolate surface-active lecithin, the phospholipids are separated on a thin rod of refractory and chemically stable material, having an outer coating of a bonded, sintered partition medium. Two solvent systems are used to develop the chromatograms, chloroform/methanol/water to separate lecithin and sphingomyelin, tetrahydrofuran/methylal/methanol for phosphatidylglycerol. Then the rod is passed through an hydrogen flame; the resulting ions produced generate a current, which is amplified and fed to a potentiometric recorder. The height of integral curves was proportional to the area under each peak. For quantitation we used an internal standard (lysolecithin in the first system. phosphatidyldimethylethanolamine in the second). The method requires less than 5 mL of amniotic fluid; results are available within 6 h.

The study consists in adapting two methods allowing estimation of proteins in cerebrospinal fluid and urine on a centrifugal analyzer using Coomassie Blue-SDS and benzethonium chloride. Results obtained with the two reagents are compared with turbidimetric technic using trichloroacetic acid, by statistic methods.

During organic acid screening by gas chromatography/mass spectrometry, we detected a large peak corresponding to glyceric acid in a patient's urine sample. The D(+) configuration was demonstrated by a polarimetric method and by enzymatic stereospecificity of D-glycerate dehydrogenase (EC 1.1.1.29). We biochemically investigated this fifth reported case of D-glyceric acidemia. In our patient, loading tests with L-serine and fructose led to an increase of D-glyceric acid in both plasma and urine. Determination of other metabolites involved in D-glycerate metabolism revealed no abnormality in any sample examined. After comparing all our results with those of the preceding observations described in the literature, we suggest a possible enzymatic defect located on one of the metabolic pathways shared by fructose and L-serine, possibly at the level of hepatic D-glycerate kinase (EC 2.7.1.31). Nevertheless, a primary defect of L-serine catabolism cannot be entirely excluded.