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A Cronister

Publications and source records attributed to A Cronister.

8 recordsLinked to original sources

Expanding the role of the genetic counselor.

The basic components of genetic counseling are informational and educational. The patient's cognitive and emotional presentation and the needs and concerns of the patient are seldom addressed. Females who carry the FMR1 pre and full gene mutation may present with learning, cognitive, and/or emotional difficulties and family members of those diagnosed with fragile X syndrome have ongoing needs and concerns. As a results, genetic counseling for fragile X syndrome offers a unique opportunity within which to expand the role of the genetic counselor. Q-methodology, by using the q-sort, is centered on the family to reproduce the needs and concerns that are consistent with the patient's own experience. Used for sociological research, the q-methodology with specially constructed q-sort items is easily adapted to the genetic counseling setting and can be used for directly assessing the patient's needs and concerns. For our pilot study, 16 items were physically sorted and ranked interdependently by the patient (subject). Thirty-seven patients (29 females and 8 males) participated in our pilot study. Preliminary results show that the age of the proband, length of time of the diagnosis, and parental sex at the time the q-sort is administered impacts the ranking of items thus differentiating needs and concerns. Results have shown that specific items are missing from the lives of subjects. From the information obtained from the q-sort, the genetic counselor can identify needs and concerns of the patient and combine this information with the clinical presentation to work with the patient in a more effective manner.

Adult↗

Dissemination of genetic risk information to relatives in the fragile X syndrome: guidelines for genetic counselors.

Fragile X Syndrome, which affects 1 in 1,250 males, is the most common inherited condition causing mental retardation. Although carrier detection for the fragile X syndrome utilizing DNA has now been simplified, genetic counseling and the process of informing at-risk family members remains complex. The purpose of this paper is to offer practical guidelines to health professionals providing genetic counseling to fragile X families in order to facilitate the dissemination of genetic risk information to relatives. This paper was developed from a workshop held at the 4th International Fragile X Conference. The guidelines presented here represent a beginning in the development of an approach to informing relatives in fragile X families about genetic risk, and the identification of mechanisms to reduce the burden to families.

Family↗

Direct mutation analysis of 495 patients for fragile X carrier status/proband diagnosis.

With the cloning of the FMR-1 gene, direct mutation analysis is possible for fragile X syndrome. We have analyzed 495 patients using the StB12.3 probe/EcoRI/EagI system of Rousseau et al. [N Engl J Med 325:1673-1681, 1991] and 167 of these also with PCR analysis according to Brown et al. [JAMA 270:1569-1575, 1993]. For 28 patients requesting carrier status due to a family history of fragile X, 10 were shown to have either premutations or full mutations; for the remainder with varied backgrounds, 1 in 182 was shown to carry a premutation. For proband diagnosis, 7 of 14 with a fragile X family history carried a full mutation; 11 of 271 with other family histories carried the full mutation.

Blotting, Southern↗

Oral-facial-digital syndrome type VI (Váradi syndrome): further clinical delineation.

Cerebellar anomalies are consistent findings in patients with the oral-facial-digital syndrome type VI (Váradi syndrome) in addition to variable facial and oral changes, and polysyndactyly of hands and feet. We report 3 unrelated patients with this entity who have a hypoplastic cerebellar vermis shown by magnetic resonance imaging (MRI), as well as clinical signs of cerebellar defect. Polydactyly of the hands is characterized by a central Y-shaped metacarpal. Clinically recurrent episodes of tachypnea and hyperpnea are remarkable. Postnatal growth is delayed with short stature in all 3 patients possibly due to growth hormone deficiency in one of them. In contrast to reported patients who are all severely mentally retarded, one of our patients is of normal intelligence. Type VI oral-facial-digital syndrome is an autosomal-recessive trait and may be detected prenatally.

Abnormalities, Multiple↗

Parental inheritance and psychological disability in fragile X females.

Studies of adult female carriers of the fragile X chromosome indicate that certain psychological problems occur with a greater frequency and severity than expected. This study examines the association of parental origin of the fragile X chromosome and of fragility detected in the karyotype with measures of social, educational, and psychological functioning in a group of adult fragile X females of normal intelligence. The results show that, as a group, women who inherit the fragile X chromosome from their mother and who demonstrate positive fragility in the karyotype (MI+ group = [maternal inheritance with positive fragility]) manifest significantly more impairment of social, educational, and psychological functioning when compared with fragile X females with paternal inheritance or negative fragility or with a matched control group comprising non-fragile X women. In particular, MI+ women show lower levels of both educational achievement and socioeconomic status and a greater degree of disturbance in communication, socialization, affect, and thought processes. These clinical findings are consistent with the recently advanced hypothesis which proposes that a two-stage process leading to chromosome imprinting in a preoogonial cell causes the fragile X syndrome.

Anxiety Disorders↗

Heterozygous fragile X female: historical, physical, cognitive, and cytogenetic features.

Historical, physical, cognitive, and cytogenetic data were documented in 105 heterozygous fragile X [fra(X)] females and 90 controls in a prospective fashion. For comparisons, we divided heterozygotes and controls into those with cognitive impairment (IQ less than 85) and normal IQ (IQ greater than or equal to 85). The only finding that was significantly more frequent in impaired heterozygotes compared with impaired controls chi 2 analysis was shyness. Features that were more frequent in normal IQ heterozygotes compared with normal controls were voluntary thumb dislocation and hyperextensible metacarpal-phalangeal (MP) joints. Comparisons among heterozygotes demonstrated more math problems, hand biting, strabismus, high-arched palate, hyperextensible finger joints, and flat feet in impaired heterozygotes than in normal heterozygotes. Premature menopause was present in 8 of 61 normal heterozygotes and in none of the impaired heterozygotes. A multiple regression analysis demonstrated a significant inverse correlation between the percent fragility and IQ for the heterozygotes as a group. However, no correlation existed between IQ and fragility when the percent fragility was 2% or greater. However, a higher percentage of fragility was positively correlated with the total number of physical findings present.

Adolescent↗

Fragile X checklist.

A 13-item checklist that combines physical and behavioral traits typical of fragile X [fra(X)] syndrome was evaluated prospectively in the screening of 107 males with mental retardation or severe learning disabilities. The checklist was completed before we obtained cytogenetic results. Fifteen males were fra(X)-positive and the manifestations that differentiated fra(X)-positive and fra(X)-negative patients included perseverative speech, large or prominent ears, large testicles, and tactile defensiveness. The combination of physical and behavioral traits is helpful in suggesting the diagnosis and identifying high-risk patients. A total score of 16 or higher had a significant yield of fra(X)-positive patients (greater than or equal to 45%).

Age Factors↗

Mental impairment in cytogenetically positive fragile X females.

Prenatal diagnosis is now available to fragile X (fra[X]) syndrome families and has proven reliable when testing male fetuses. It has been reported that approximately one-third of heterozygous fra(X) females demonstrate mental impairment. Based on this, families usually continue pregnancies involving a female fetus. The purpose of this study is to investigate whether a 35% risk for mental impairment is appropriate when counseling heterozygous women carrying fra(X)-positive female fetuses. Forty-three cytogenetically positive (greater than or equal to 2%) daughters of known fra(X) carrier women were ascertained postnatally in an unbiased fashion. Their mother's carrier status was determined on the basis of at least one son with Martin-Bell syndrome. In addition to peripheral blood cytogenetic studies, all daughters had cognitive testing to determine full-scale IQ. In this study, 55.8% (24/43) were mentally impaired (IQ less than 85) compared with the expected 35%. Of these, 42% were mentally retarded (IQ less than 70). Although we do not know the correlation between percent fragility by peripheral blood compared with the percent fragility by amniocentesis or CVS, we assume that they are relatively comparable such that a female who is positive with greater than or equal to 2% fragility would probably be positive by all methods. This report suggests that the penetrance of mental impairment in females with a percent fragility of greater than or equal to 2% may be as high as 55%. Further studies are necessary to clarify this issue so that accurate information can be given in genetic counseling.

Adolescent↗