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[Medico-genetical study of the Uzbekistan population. IX. Variability of hereditary pathology, territorial distribution of hereditary diseases and hereditary disease load in the population of the Urgut district of the Samarkand region].

Medical-genetic study was carried out in the population of Samarkand province (the population size about 150 000). Hereditary pathology was ascertained among families with two or more affected members with chronic diseases. 110 families with 210 patients were registered. The most frequent were autosomal-recessive disorders (42 nozological forms). 15 nozological forms are probably "new" conditions in this province, because they were absent in our previous medical-genetic study of this province. A tendency to local accumulation of families with the same disorder in small populations was observed. The load of autosomal-recessive disorders comprised 2.2 X 10(-3) affected, that of autosomal-dominant disorders being 0.51 X 10(-3) and of X-linked disorders being 0.25 X 10(-3) males. The importance of assortative maitings in manifestation of rare autosomal-recessive genes in Uzbek population is discussed.

Female↗

Hereditary pancreatitis and the risk of pancreatic cancer. International Hereditary Pancreatitis Study Group.

BACKGROUND: Hereditary pancreatitis is an autosomal-dominant disease, with a variable expression and an estimated penetrance of 80%. The gene for this disease has recently been mapped to chromosome 7q35, and the defect is believed to be caused by a mutation in the cationic trypsinogen gene. Acute attacks of abdominal pain begin early in life and the disease often progresses to chronic pancreatitis. Although the risk of pancreatic cancer is thought to be increased in more common types of chronic pancreatitis, the frequency of pancreatic cancer in the inherited type of pancreatitis is uncertain. PURPOSE: The aim of this study was to assess the frequency of pancreatic cancer and other tumors in patients with hereditary form of pancreatitis. METHODS: To determine the natural history of hereditary pancreatitis, we invited all members of the American Pancreatic Association and the International Association of Pancreatology to participate in a longitudinal study of this rare form of pancreatitis. The initial criteria for patient eligibility were as follows: early age (< or = 30 years) at onset of symptoms, positive family history, and absence of other causes. From April 1995 through February 1996, 37 physicians from 10 countries contributed medical records of 246 (125 males and 121 females) patients thought to have hereditary pancreatitis as the most likely diagnosis. This group included 218 patients where the diagnosis appeared to be highly probable and 28 additional patients where the diagnosis of hereditary pancreatitis was less certain: 25 patients who had relatively late onset of disease and a positive family history and three patients with onset of disease before age 30 years but with an uncertain family history. We reviewed all causes of death and compared the observed to the expected frequency of cancer in this historical cohort of patients with hereditary pancreatitis. The strength of the association between pancreatitis and pancreatic cancer was estimated by the standardized incidence ratio (SIR), which is the ratio of observed pancreatic cancer cases in the cohort to the expected pancreatic cancers in the background population, adjusted for age, sex, and country. RESULTS: The mean age (+/- standard deviation [SD]) at onset of symptoms of pancreatitis was 13.9 +/- 12.2 years. Compared with an expected number of 0.150, eight pancreatic adenocarcinomas developed (mean age +/- SD at diagnosis of pancreatic cancer: 56.9 +/- 11.2 years) during 8531 person-years of follow-up, yielding an SIR of 53 (95% confidence interval [CI] = 23-105). The frequency of other tumors was not increased: SIR = 0.7 (95% CI = 0.3-1.6). Eight of 20 reported deaths in the cohort were from pancreatic cancer. Thirty members of the cohort have already been tested for the defective hereditary pancreatitis gene: all 30 carry a mutated copy of the trypsinogen gene. The transmission pattern of hereditary pancreatitis was known for 168 of 238 patients without pancreatic cancer and six of eight with pancreatic cancer. Ninety-nine of the 238 patients without pancreatic cancer and six of the patients with pancreatic cancer inherited the disease through the paternal side of the family. The estimated cumulative risk of pancreatic cancer to age 70 years in patients with hereditary pancreatitis approaches 40%. For patients with a paternal inheritance pattern, the cumulative risk of pancreatic cancer is approximately 75%. CONCLUSIONS: Patients with hereditary pancreatitis have a high risk of pancreatic cancer several decades after the initial onset of pancreatitis. A paternal inheritance pattern increases the probability of developing pancreatic cancer.

Adolescent↗

Suspected hereditary nonpolyposis colorectal cancer: International Collaborative Group on Hereditary Non-Polyposis Colorectal Cancer (ICG-HNPCC) criteria and results of genetic diagnosis.

PURPOSE: The aim of this study was to determine the frequency of mutations in the mismatch repair genes in families suspected of having hereditary nonpolyposis colorectal cancer. METHODS: We devised two criteria for families suspected of having hereditary nonpolyposis colorectal cancer (Criteria I and II). Criteria I consist of at least two first-degree relatives affected with colorectal cancer with at least one of the following: development of multiple colorectal tumors including adenomatous polyp, at least one colorectal cancer case diagnosed before the age of 50, and occurrence of a hereditary nonpolyposis colorectal cancer extracolonic cancer (endometrium, urinary tract, small intestine, stomach, hepatobiliary system, or ovary) in family members. Criteria II consist of one colorectal cancer patient with at least one of the following: early age of onset (<40 years); endometrial, urinary tract, or small intestine cancer in the index patient or a sibling (one aged <50 years); and two siblings with other integral hereditary nonpolyposis colorectal cancer extracolonic cancers (one aged <50 years). A questionnaire was mailed to members of the International Collaborative Group on Hereditary Non-Polyposis Colorectal Cancer to determine the mutation detection rate in mismatch repair genes from the families fulfilling these criteria. For comparison the mutation detection rate for families fulfilling the Amsterdam hereditary nonpolyposis colorectal cancer criteria in each institution was also obtained. RESULTS: Data were obtained from eight different institutions (in 7 different countries). In a total of 123 patients from 123 families (67 families fulfilling Criteria I and 56 families fulfilling Criteria II), genetic testing for germline mismatch repair gene variants was performed. Germline mutations of the hMLH1 or hMSH2 genes were identified in 24 families (20 percent). Of these, the mutation detection rate for families fulfilling Criteria I was 28 percent (19/67). The mutation detection rate for families fulfilling Criteria II was 9 percent (5/56). In these eight institutions, the overall mutation detection rate for families fulfilling the Amsterdam hereditary nonpolyposis colorectal cancer criteria was 50 percent (77/154). CONCLUSION: The Criteria I for suspected hereditary nonpolyposis colorectal cancer have the advantages that they can be applied to nuclear families and they can include extracolonic cancers. The results of this study suggest that families fulfilling Criteria I should be offered genetic testing. The relatively low mutation detection rate in those families fulfilling Criteria II suggests that, using current techniques, genetic testing in these families is not practical.

Age of Onset↗

Clonal karyotypic abnormalities of the hereditary multiple exostoses chromosomal loci 8q24.1 (EXT1) and 11p11-12 (EXT2) in patients with sporadic and hereditary osteochondromas.

BACKGROUND: Osteochondroma most frequently arises sporadically and as a solitary lesion, but also may arise as multiple lesions characterizing the autosomal dominant disorder hereditary multiple exostoses (HME) and the contiguous gene syndromes Langer-Giedion and DEFECT-11 syndromes. HME is genetically heterogeneous with association of three loci including 8q24.1 (EXT1), 11p11-12 (EXT2), and 19p (EXT3). Constitutional chromosomal microdeletions of 8q24.1 and 11p11-12 are features of the Langer-Giedion and DEFECT-11 syndromes, respectively. Cytogenetic studies of osteochondroma are rare. METHODS: Cytogenetic analysis was performed on 34 osteochondroma specimens from 22 patients with sporadic lesions and 4 patients with HME utilizing standard methodologies. Fluorescence in situ hybridization with chromosome specific probes was performed on three cases to define structural rearrangements further. RESULTS: Clonal abnormalities were detected in ten cases. Notably, deletion of 11p11-13 was observed in one case (a sporadic tumor) and loss or rearrangement of 8q22-24.1 in eight cases (seven sporadic and one hereditary tumor). CONCLUSIONS: These findings: 1) confirm previous observations of 8q24.1 karyotypic anomalies in sporadic osteochondroma, 2) reveal the presence of somatic chromosomal anomalies in hereditary osteochondromata, 3) suggest that similar to hereditary lesions, sporadic osteochondromas also are genetically heterogeneic (involvement of both 8q24.1 and 11p11-12), and 4) support the hypothesis that loss or mutation of EXT1 and EXT2, two putative tumor suppressor genes, may be important in the pathogenesis of sporadic as well as hereditary osteochondromata.

Adolescent↗

Frequency of extra-colonic tumors in hereditary nonpolyposis colorectal cancer (HNPCC) and familial colorectal cancer (FCC) Brazilian families: An analysis by a Brazilian Hereditary Colorectal Cancer Institutional Registry.

UNLABELLED: The two main forms of hereditary colorectal cancer are familial adenomatous polyposis (FAP) and hereditary nonpolyposis colorectal cancer (HNPCC). Some families do not meet all the diagnostic criteria for HNPCC or FAP and are classified as familial colorectal cancer (FCC). Little information is available on the spectrum of tumors related to HNPCC and FCC in South America. OBJECTIVE: To describe the frequency of malignant tumors in a group of Brazilian families with HNPCC or FCC in an Institutional Hereditary Colorectal Cancer Registry. MATERIAL AND METHODS: The study included 61 families (29 HNPCC and 32 FCC) between January 1998 and June 2001. HNPCC families were clinically classified according to the Amsterdam Criteria I or II. FCC families were characterized by the presence of at least two individuals with CRC or extra-colonic tumors associated with the HNPCC spectrum, at least one of them being under 50 years of age. RESULTS: In the 29 families with HNPCC, 201 patients with cancer were identified among 1241 individuals (589 men and 652 women). Among the 201 patients 223 tumors were observed: 137 CRC (55 in men and 82 in women) and 86 extra-colonic (37 in men and 49 in women). In the 32 families with FCC, 146 patients with cancer were identified among 1053 individuals (505 men and 548 women); 158 tumors were observed in 146 patients, 75 CRC (33 in men and 42 in women) and 83 extra-colonic tumors (47 in men and 36 in women). The most frequent extra-colonic primary sites among the HNPCC families were: endometrium (26.5%) and breast (26.5%) (women), and stomach (35.1%) (men). Among the FCC families, the most common primary sites were: breast (27.8%) (women), and stomach (44.4%) (men). CONCLUSION: The high frequency of endometrial and gastric cancer found was expected, since these tumors are part of the HNPCC spectrum, but the high frequency of breast cancer requires further molecular investigation to determine a possible hereditary predisposition associated with hereditary CRC.

Adenomatous Polyposis Coli↗

Role of detection of microsatellite instability in Chinese with hereditary nonpolyposis colorectal cancer or ordinary hereditary colorectal cancer.

AIM: To detect microsatellite instability (MSI) in patients with hereditary nonpolyposis colorectal cancer or ordinary hereditary colorectal cancer and to provide criteria for screening the kindreds with hereditary nonpolyposis colorectal cancer at molecular level. METHODS: MSI was detected in the specimens from 20 cases with HNPCC, 20 cases with ordinary hereditary colorectal cancer and 20 cases with sporadic colorectal cancer by means of polymerase chain reaction-single strand conformation polymorphism. RESULTS: The positive rate of MSI was 85% (17/20) in HNPCC group, 40% (8/20) in ordinary hereditary colorectal cancer group and 10% (2/20) in the sporadic colorectal cancer group respectively. The differences were significant. The mean ages of the three groups were 43.6, 52.2, and 61.8 years respectively, which increased gradually. The incidence of right hemicolon cancer was 64.7%, 37.5%, and 0% respectively, which decreased gradually and had significant difference. The expression ratio of BAT26 and BAT25 was 94.1% respectively, which was highest in the 5 gene sites studied. The incidence of poorly differentiated adenocarcinoma was 70.6% in HNPCC group among high frequency microsatellite instability (MSI-H), which was higher than the other two groups, which had 50% and 50% respectively. CONCLUSION: The incidence of MSI-H is higher in HNPCC group. The detection of MSI is simple and economical and has high correlation with the clinicopathologic feature of HNPCC and can be used as a screening method to detect the germ line mutation of the mismatch repair gene.

Adult↗

[Hereditary predisposition of colorectal cancer and prevalence of hereditary nonpolyposis colorectal cancer in general population of colorectal cancer patients in China].

OBJECTIVE: To analyze hereditary predisposition of CRC and the prevalence of HNPCC in general population of CRC patients in China. METHODS: CRC patients were from two sources. One is that we consecutively investigated 594 patients by ourselves. They were proved to be colorectal cancer by histology. The following data of all patients should be registered: sex, age diagnosed colorectal cancer, site, number and histological type of primary cancer. The other was the published Chinese and foreign literatures related to Chinese HNPCC prevalence, and there were cumulatively 3596 patients in all. Hereditary predisposition of CRC (or malignant tumors) is that CRC patients have two or more first- or second-degree relatives (or both) with CRC (or malignant tumors). HNPCC was diagnosed by Amsterdam Criteria I (AC I) or Amsterdam Criteria II (AC II), Japanese Criteria of HNPCC (JC). RESULTS: Hereditary predisposition of both malignant tumors and CRC were 17.2% and 5.2% in 594 patients with CRC, respectively. Multiple primary cancers and multiple CRC were 13.1% and 10.1% , respectively. Among them, multiple primary cancers and multiple CRCs without familial history were 9.1% and 6.7%, respectively. There was a correlation between familial history of malignant tumors and multiple primary cancers and multiple CRCs (both P < 0.01). Patients with familial history of malignant tumors had more frequently multiple primary cancers and multiple CRCs than patients without history of malignant tumors. Younger patients (< or = 50) were 21.4% in all CRC patients. there was a correlation between younger patients (< or =50) and familial history of malignant tumors and familial history of CRC (both P < 0.05). When CRC was diagnosed, patients with familial history of malignant tumors and familial history were younger than patients without them. In the population of CRC patients in China, prevalence of HNPCC diagnosed AC I, AC II and JC were 1.24%, 2.15% and 2.93%, respectively. CONCLUSIONS: Hereditary predispositions of malignant tumors and CRC were 17.2% and 5.2% in CRC patients, respectively. Familial history of malignant tumors, multiple primary cancers and younger patients with CRC (< or =50) were the clinical markers of hereditary predisposition of malignant tumors including CRC. Multiple primary cancers and younger patients with CRC (< or =50) were all correlated with familial history of malignant tumors. The prevalence of HNPCC in China was similar to that in Western countries.

Adult↗

Protein patterns of cerebrospinal fluid in hereditary ataxias and hereditary spastic paraplegia.

The CSF findings in hereditary ataxias and allief disorders have hitherto mostly been reported as normal if one excludes Refsum's syndrome. The CSF-protein patterns found on isoelectric focusing and quantitative paper electrophoresis were studied in 12 patients with hereditary ataxias and hereditary spastic paraplegia. Using a recently-developed technique of isoelectric focusing of CSF-proteins in flat beds of polyacrylamide gel, the authors could show abnormal CSF-protein patterns in all but 1 of the present cases. The aberrant CSF-protein patterns found showed differences between the syndromes studied. Two unique patterns with conspicuous fractions in the acid range were observed in patients with Marie-Sanger-Brown's ataxia (mother and daughter) and Holmes' ataxia. A third CSF-protein pattern was found in a sibship with Friedreich's ataxia including a double fraction in the acid region (pI 5.9-6.1) in all 4 subjects and a highly alkaline fraction (HAF) with pI about 9.3, in 3 of them. Similar acid fractions (pI 5.9-6.1) were also detected in 3 of 4 patients with hereditary spastic paraplegia, a brother and sister showing a very similar CSF-protein pattern. Double fractions with pI 5.9-6.1 and/or HAF may also occur in other neurological diseases, mostly, however, associated with other distinctive features of their CSF-protein patterns. A possibility in the future of distinguishing hereditary CNS-diseases by examination of the CSF-protein pattern is suggested.

Abetalipoproteinemia↗

Mutations of the cationic trypsinogen gene in hereditary and non-hereditary pancreatitis.

BACKGROUND/AIMS: Mutations in the cationic trypsinogen gene have been detected in patients with hereditary pancreatitis (HP). This study investigates the prevalence of the R122H, N29I, A16V and -28delTCC mutations in the common, non-hereditary forms of chronic pancreatitis and in a HP family. METHODS: DNA was prepared from blood samples of 53 patients with chronic pancreatitis (36 alcoholic, 14 idiopathic and 3 hereditary), 20 alcoholic controls and 20 healthy, ethnically matched controls. The R122H and A16V mutations were identified by the polymerase chain reaction (PCR) and restriction enzyme digestion. A nested-PCR was used to identify the N29I mutation. The -28delTCC deletion and the C133807T polymorphism were sought by direct sequencing. RESULTS: The R122H mutation was detected in 1 patient with alcoholic chronic pancreatitis and all 3 affected members of a HP family. The N29I, A16V and -28delTCC mutations were not detected in any of the study subjects. At the C133807T polymorphism, the C allele and C/C genotype were significantly increased in alcoholic chronic pancreatitis (p = 0.001 and p = 0.0004, respectively) while the T allele and CT genotype were significantly reduced (p = 0.001 and p = 0.004, respectively) compared to healthy controls. CONCLUSIONS: Mutations of the cationic trypsinogen gene are rarely found in chronic pancreatitis patients of typical aetiology. Screening for these mutations should be considered in those with a family history consistent with hereditary pancreatitis but may also be appropriate in a well-defined subgroup of patients with non-hereditary chronic pancreatitis, i.e. those who have developed the disease before the age of 30.

Adult↗

[Hereditary protein lithiasis and calcium lithiasis: two different forms of hereditary pancreatitis].

We previously reported that the most frequent cases of chronic pancreatitis were the consequence of pancreatic lithiasis and that there were different forms of pancreatic lithiasis with different etiologies and composition of calculi. The most frequent form is the calcic lithiasis, generally due to nutritional disorders. The second most frequent form is proteic lithiasis. In this paper, we report 1.) Ten hereditary cases on a total of 36 patients presenting with proteic lithiasis (age at clinical onset 15 +/- 12 years); 2.) one hereditary case on a total of 150 patients with proteic lithiasis. In these two different maladies, the transmission seems to be dominant, autosomal with incomplete penetrance. Hereditary pancreatitis is therefore a group of at least two different diseases, hereditary protein lithiasis, the most frequent one and hereditary calcic lithiasis exceptional.

Adolescent↗

Failure to diagnose hereditary colorectal cancer and its medicolegal implications: a hereditary nonpolyposis colorectal cancer case.

PURPOSE: We describe a patient who had precancerous colonic symptoms and a positive family history of multiple occurrences of early-onset colorectal cancer in her first-degree and second-degree relatives consistent with hereditary nonpolyposis colorectal cancer. Hereditary nonpolyposis colorectal cancer diagnosis had not been made before her diagnosis of carcinoma of the cecum with liver metastasis. She died at age 20, leading to litigation. Controversies about standards of care, their malpractice implications, and pertinent legal issues are discussed. METHODS: Review of the medical and family history was made by the expert witness (HTL) with appropriate documentation of the chronology of symptoms, as derived from depositions. These documents revealed that the patient's mother had repeatedly discussed with the caregivers her concern about the family history of colon cancer and the need for appropriate surveillance. RESULTS: The patient's colonic symptoms progressed for a period of three years. Flexible sigmoidoscopy was performed by a nonphysician. The physician who ordered the procedure considered this appropriate because isolated polyps were reported in the patient's father and paternal uncle, which apparently led him to believe that the diagnosis was familial adenomatous polyposis. During litigation procedures, a pedigree was constructed and found to be consistent with hereditary nonpolyposis colorectal cancer. The case was settled in favor of the plaintiff before trial. CONCLUSION: It is essential to understand the natural history of hereditary nonpolyposis colorectal cancer, inclusive of the need for surveillance colonoscopy in patients at increased risk by virtue of their position in their family pedigree.

Adenomatous Polyposis Coli↗

Hereditary non-polipomatous colorectal cancer: hereditary predisposition, diagnosis and prevention.

BACKGROUND: Colorectal cancer is the third in frequency and the second in mortality in developed countries. In Brazil, it is among the six more common malignant neoplasias. About 20% of colorectal tumors have some hereditary component. AIM: This study presents a review of genetic and clinic aspects, as well as diagnosis and prevention of the hereditary non-polipomatous colorectal cancer, that is the more frequent form of hereditary colorectal cancer. This approach is important because, currently there are possibilities of management, prevention and surveillance specific to individuals at-risk for hereditary non-polipomatous colorectal cancer that can lead to a great improvement in patients' survival and their at-risk relatives.

Colorectal Neoplasms, Hereditary Nonpolyposis↗

Spectrin mutations in hereditary elliptocytosis and hereditary spherocytosis.

Hereditary elliptocytosis (HE), its aggravated form hereditary pyropoikilocytosis (HPP), and hereditary spherocytosis (HS) designate a set of congenital hemolytic syndromes. The responsible mutations lie in several genes encoding proteins of the red cell membrane. In particular, they involve the SPTA1 and SPTB genes that encode erythroid spectrin alpha- and beta-chains, respectively. In situ, spectrin is a alpha 2 beta 2 fibrillar tetramer resulting from the head-to-head self-association of two alpha beta dimers. In HE, the 24 known alpha-chain mutations lie in the self-association site or its vicinity, whereas the 17 beta-chain mutations occur in the self-association site itself (record of November 30, 1995). Allele alpha LELY (LELY: Low Expression LYon) is found in ethnic groups remote from one another with a uniform frequency (20-30% of all alpha-alleles). It allows an expanded expression of any HE alpha-allele located in trans and results in severe HE or in HPP. In HS, a number of spectrin mutations have been recorded recently. Allele alpha LEPRA (LEPRA: Low Expression PRAgue) would occur in a recurrent fashion.

Elliptocytosis, Hereditary↗

Germ line mutations of mismatch repair genes in hereditary nonpolyposis colorectal cancer patients with small bowel cancer: International Society for Gastrointestinal Hereditary Tumours Collaborative Study.

PURPOSE: The aim of study was to determine the clinical characteristics and mutational profiles of the mismatch repair genes in hereditary nonpolyposis colorectal cancer (HNPCC) patients with small bowel cancer (SBC). EXPERIMENTAL DESIGN: A questionnaire was mailed to 55 members of the International Society for Gastrointestinal Hereditary Tumours, requesting information regarding patients with HNPCC-associated SBC and germ line mismatch repair gene mutations. RESULTS: The study population consisted of 85 HNPCC patients with identified mismatch repair gene mutations and SBCs. SBC was the first HNPCC-associated malignancy in 14 of 41 (34.1%) patients for whom a personal history of HNPCC-associated cancers was available. The study population harbored 69 different germ line mismatch repair gene mutations, including 31 mutations in MLH1, 34 in MSH2, 3 in MSH6, and 1 in PMS2. We compared the distribution of the mismatch repair mutations in our study population with that in a control group, including all pathogenic mismatch repair mutations of the International Society for Gastrointestinal Hereditary Tumours database (excluding those in our study population). In patients with MSH2 mutations, patients with HNPCC-associated SBCs had fewer mutations in the MutL homologue interaction domain (2.9% versus 19.9%, P = 0.019) but an increased frequency of mutations in codons 626 to 733, a domain that has not previously been associated with a known function, versus the control group (26.5% versus 2.8%, P < 0.001). CONCLUSIONS: In HNPCC patients, SBC can be the first and only cancer and may develop as soon as the early teens. The distribution of MSH2 mutations found in patients with HNPCC-associated SBCs significantly differed from that found in the control group (P < 0.001).

Adaptor Proteins, Signal Transducing↗

Molecular genetics of hereditary elliptocytosis and hereditary spherocytosis.

Red cells ow their mechanical properties, that is, their resistance and their elastic deformability, to a protein network that laminates the lipid bilayer and to proteins spanning the latter. All proteins are interconnected. Their structure, as well as the structure of the corresponding genes, will be outlined. Numerous mutations have allowed to reclassify hereditary elliptocytosis (HE) and poikilocytosis (HP), and, more recently, hereditary spherocytosis (HS) into well defined subsets of hereditary hemolytic anemias. HE stems from changes in the SPTA1, SPTB, EL1 and (exceptionally) GPYC genes that encode spectrin alpha- and beta- chains, protein 4.1 and glycophorin C/D, respectively. HS derives from altercations in the ANK1, EPB3 and ELB42 genes, encoding ankyrin, band 3 and protein 4.2, respectively, and also in the SPTA1 and SPTB genes. We will present a repertory of the known mutations. Innumerable polymorphisms will not be considered here, except for a few remarkable ones. Some general points must be stressed on. (a) Clinically conspicuous disorders are often the result of two alleles interacting in trans to one another. Whereas one allele causes moderate symptoms by itself, the other one is usually silent in the simple heterozygous (and exceptionally in the homozygous) state. As a result, the number of potentially pathogenic alleles is much more important than had been initially suspected. (b) The reduction or the loss of a protein within multiprotein assemblies are frequently encountered in red cell membrane genetic diseases; it leads to the disruption of the complexes with the possible disappearance of the other proteins than the mutated protein. (c) The above genes being also expressed in nonerythroid tissues, one starts finding multisyndromic conditions adding non-hematological manifestations to hemolysis. It is puzzling, though, that such situations are not more frequent. (d) In practice, the molecular diagnosis of HE and HS has reached a semi-routine stage that helps very much the paediatricians and haematologists.

Anemia, Hemolytic↗