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Context: Autosomal dominant inactivating sprouty-related EVH1 domain-containing protein 1 (SPRED1) mutations have recently been described in individuals presenting mainly with café au lait macules (CALMs), axillary freckling, and macrocephaly. The extent of the clinical spectrum of this new disorder needs further delineation.Objective: To determine the frequency, mutational spectrum, and phenotype of neurofibromatosis type 1-like syndrome (NFLS) in a large cohort of patients.Design, Setting, and Participants: In a cross-sectional study, 23 unrelated probands carrying a SPRED1 mutation identified through clinical testing participated with their families in a genotype-phenotype study (2007-2008). In a second cross-sectional study, 1318 unrelated anonymous samples collected in 2003-2007 from patients with a broad range of signs typically found in neurofibromatosis type 1 (NF1) but no detectable NF1 germline mutation underwent SPRED1 mutation analysis.Main Outcome Measures: Comparison of aggregated clinical features in patients with or without a SPRED1 or NF1 mutation. Functional assays were used to evaluate the pathogenicity of missense mutations.Results: Among 42 SPRED1-positive individuals from the clinical cohort, 20 (48%; 95% confidence interval [CI], 32%-64%) fulfilled National Institutes of Health (NIH) NF1 diagnostic criteria based on the presence of more than 5 CALMs with or without freckling or an NF1-compatible family history. None of the 42 SPRED1-positive individuals (0%; 95% CI, 0%-7%) had discrete cutaneous or plexiform neurofibromas, typical NF1 osseous lesions, or symptomatic optic pathway gliomas. In the anonymous cohort of 1318 individuals, 34 different SPRED1 mutations in 43 probands were identified: 27 pathogenic mutations in 34 probands and 7 probable nonpathogenic missense mutations in 9 probands. Of 94 probands with familial CALMs with or without freckling and no other NF1 features, 69 (73%; 95% CI, 63%-80%) had an NF1 mutation and 18 (19%; 95% CI, 12%-29%) had a pathogenic SPRED1 mutation. In the anonymous cohort, 1.9% (95% CI, 1.2%-2.9%) of individuals with the clinical diagnosis of NF1 according to the NIH criteria had NFLS.Conclusions: A high SPRED1 mutation detection rate was found in NF1 mutation-negative families with an autosomal dominant phenotype of CALMs with or without freckling and no other NF1 features. Among individuals in this study, NFLS was not associated with the peripheral and central nervous system tumors seen in NF1. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine the level of beta-thalassemia awareness among Italians living on the eastern side of Sicily (Bronte, Catania, and Tortorici, Messina), Italian-Americans, and Americans of other ethnic backgrounds (Other-Americans). A questionnaire was developed which asked respondents knowledge questions about both beta-thalassemia and Down Syndrome. Five hundred questionnaires were distributed, and 456 were ultimately returned and analyzed (150 Italians, 156 Italian-Americans, 150 Other-Americans). Italians answered an average of 55% of the beta-thalassemia correctly compared to scores of 17 and 24% for the Italian-Americans and Other-Americans, respectively. The groups did not differ in their knowledge of Down Syndrome (all answered between 58 and 60% of the questions correctly on average). Over 80% of the Italian respondents had heard of beta-thalassemia compared to only 19% of the Italian-Americans. beta-Thalassemia education programs in Italy appear to have dramatically increased awareness of the disorder. Similar programs need to be developed for at-risk populations in the United States.

The uses of systemically-based psychotherapeutic methods in genetic counseling are discussed in the context of the origin of genetic counseling, the definition of genetic counseling, and the adjustments that one must make in order to implement these methods. Selected systemic methods which can be readily incorporated into genetic counseling are presented: use of genograms to explore family attitudes and beliefs about genetic risk, communications skills, and applications of family of origin work in genetic counseling. The need for research regarding the methodology and process of genetic counseling is presented with discussion of the need for theories of practice for genetic counseling.

The recent identification of an abnormally amplified trinucleotide (cytosine guanine guanine) repeat in the fragile X gene (FMR-1) of males with fragile X syndrome and their carrier mothers allows the study of the mutation in individuals at risk. In this report, data on 396 patients and 35 normal controls are reported. Included in this sample are patients with no known family history of fragile X syndrome or mental retardation for whom the risks of fragile X syndrome are unclear. All 39 cytogenetically positive affected males and six females had the full mutation, as represented by a restriction fragment size increase (delta) of 500 base pairs (bp) or more within the cytosine guanine guanine repeat-bearing fragment of the FMR-1 gene; and all 16 of the normal obligate carrier females bore the premutation, as demonstrated by a delta of 100 to 500 bp. Of 124 patients (62 males and 62 females) with a family history of fragile X syndrome, five (8%) of the males and 25 (40%) of the females had the premutation. Five (2.2%) of the 231 mentally impaired patients with no confirmed family history of fragile X syndrome were found to have the full mutation. Twelve (33%) of 36 mentally impaired males and one (20%) of five females with unknown family history were found to carry an amplified cytosine guanine guanine repeat. Using this technique, we also reevaluated risk assessments previously generated by linkage analysis and unambiguously determined the carrier status of individual family members.

We report on a newborn girl with holoprosencephaly, microcephaly, absent right radius, and other anomalies with an 46,XX,i(18q) chromosome constitution. This is the first report of an i(18q) in syndromal alobar holoprosencephaly.

Here we report on 4 unrelated patients with reciprocal translocations which resulted in duplication of the distal portion of chromosome 1q. Although the patients had certain non-specific malformations in common, our investigation and a review of the literature do not suggest the existence of a distinct phenotype due to this chromosome abnormality. We think that the coexisting deletion present in each of these patients is responsible for most of the observed differences in clinical manifestations. The variable phenotype makes clinical recognition difficult and precludes making a long-term prognosis.

Silver-stained chromosomes from 29 couples with a trisomy 21 offspring and from 25 control couples were studied to determine whether there was an association of nucleolar-organizing-region variants in parents of children with trisomy 21. A reproducible scoring system for the analysis of silver-stained chromosomes was developed, and this was applied to the analysis of study participants in a blinded fashion. Seven of the 58 parents of children with trisomy 21 and seven of the 50 control parents were found to have variant NORs on silver staining. Therefore, we do not find a demonstrable risk for nondisjunction of chromosome 21 in individuals with silver-staining variants.

The first training program for genetic counselors began in 1969. Since then a number of other programs have been developed and more than 650 individuals have graduated from these programs. This article reviews the development and current status of training opportunities for genetic counselors. Twelve programs that currently grant a master's-level degree in genetic counseling are reviewed. Other areas, such as certification and licensure, that reflect genetic counseling training or such issues of professional growth as continuing education and career advances are addressed.

Recurrence of de novo GqGq Down syndrome (DS) in nine reported families and the low frequency of this chromosome abnormality in the population prompted this multicenter study to examine recurrence rate. Pedigrees and cytogenetic findings were analyzed from 112 families ascertained by a DS child with de novo GqGq translocation. Four of 112 sets of parents had abnormal cytogenetic findings. One mother and two fathers had a low proportion of mosaicism for trisomy 21 in peripheral lymphocytes. In one of these fathers, fibroblast studies confirmed the mosaicism (others not similarly studied). Two of these three families have one additional child each, both being normal. In the fourth family, the mother is heterozygous for a pericentric inversion of chromosome 21. Ninety of the 112 probands had a total of 130 full sibs and 34 half sibs. None of these 164 sibs was affected; the recurrence rate could still be as high as 2% (with 95% confidence based upon calculation of a one-tailed confidence interval). Because of the latter, the nine reports of recurrence in the literature, and the abnormal cytogenetic findings in peripheral lymphocytes in 4/112 sets of parents (3.6%), we think that caution should be exercised when counseling that the recurrence risk of this event is remote.

The question, Does the patient have a heritable disorder? is often the problem of the primary care physician. This paper presents an approach to the patient or family who possibly has a heritable disorder. Emphasis is placed on the need for appropriate planning to obtain the exact diagnosis and the resources available to the primary care physician. The role and process of genetic counseling in primary care are described.

We report a boy and his maternal uncle who have Thrombocytopenia-Absent Radius (TAR) syndrome. The mother of the propositus is normal. A maternal aunt has mild radial hypoplasia, possibly representing partial expression of the syndrome. A review of the literature shows several pedigrees in which relatives other than sibs were affected with TAR. Thus, autosomal recessive inheritance may not account for all cases and alternate modes of transmission should be considered.

This report describes a statewide program which trains family-planning personnel to provide genetic risk screening, to educate clients about potential genetic risks, and to make appropriate referrals to genetics centers. The program is unique in that training and service delivery are all done within the structure and agencies of the family-planning councils of Pennsylvania. Through the collaboration of the Pennsylvania Department of Health, the family-planning councils, and trainers from clinical genetics centers, a uniform and comprehensive program for training and service delivery has evolved. This program now provides genetic risk screening for nearly 100,000 women/year, many of whom are from groups typically underserved by genetics services.

The risk of recurrence for trisomy 21 offspring in couples with one affected child is accepted to be 1%. The rate of trisomy 21 in second- and third-degree relatives is not established. Tamaren et al [Am J Med Genet 15:393-403, 1983] reported a Down syndrome rate of 0.67% among aunts and uncles (second-degree relatives) of a Down syndrome proband. This eightfold rate increase over that for a control group can also be applied to nieces and nephews who are also second-degree relatives. One routinely discusses amniocentesis for lower risk levels; thus, should one offer amniocentesis to every sib of a trisomy 21 proband? We obtained extensive family histories on 141 trisomy 21 kinships to ascertain the rate of trisomy 21 in second-degree relatives. The rate for sibs agreed with the accepted 1% rate. Among aunts and uncles we found no trisomy 21 individuals. We conclude that the rate of trisomy 21 in second-degree relatives does not appear to be sufficiently increased to warrant routine discussion of amniocentesis with sibs of trisomy 21 individuals.