Increased prevalence of impaired fasting glucose in MEN1 gene mutation carriers.

OBJECTIVE: Multiple endocrine neoplasia type 1 (MEN1) is a hereditary syndrome characterized by parathyroid, gastroenteropancreatic, pituitary and adrenal tumours. Cardiovascular disease has been identified as an important cause of death in MEN1 patients. Menin, the product of the MEN1 gene, is a co-activator for peroxisome proliferator-activated receptor-γ and the vitamin D receptor, which are involved in glucose metabolism. We aimed to compare insulin sensitivity and prevalence of impaired fasting glucose and diabetes mellitus between MEN1 patients and controls. DESIGN: Cross-sectional study. PATIENTS: Sixty-three MEN1 gene mutation carriers (44% men, mean age 41 years) from 22 kindreds and 126 unrelated controls matched for gender, age and BMI. MEASUREMENTS: Fasting glucose levels were categorized and compared using WHO criteria. Homeostasis model assessment (HOMA) was used as a measure of insulin resistance. RESULTS: Homeostasis model assessment was significantly increased in MEN1 patients compared with controls (3·0 ± 2·0 vs 2·0 ± 1·0, P < 0·05). In MEN1 patients, HOMA was associated with BMI, but not with age, calcium and gastrin levels. Using logistic regression analysis, the presence of hyperparathyroidism, pancreatic lesions and various other manifestations was not associated with HOMA. Impaired fasting glucose was more prevalent in MEN1 compared with controls (17%vs 6%, P < 0·05). Three MEN1 patients (5%) compared with four controls (3%) were diabetic (not significant). CONCLUSIONS: Multiple endocrine neoplasia type 1 patients had decreased insulin sensitivity and higher prevalence of impaired fasting glucose compared with controls, which was unrelated to MEN1 manifestations. Impaired glucose metabolism may result in increased risk of cardiovascular disease in MEN1 patients.

Multiple endocrine neoplasia type 1: a chromatin writer's block.

Multiple endocrine neoplasia type 1 (MEN1) is caused by inactivating germ line mutations of the MEN1 tumour suppressor gene. The MEN1 gene product, menin, participates in many cellular processes, including regulation of gene transcription. As part of a protein complex that writes a trimethyl mark on lysine 4 of histone H3 (H3K4me3), menin is involved in activating gene transcription. Several functions of the menin histone methyltransferase complex have been discovered through protein interaction studies. Menin can interact with nuclear receptors and regulate transcription of hormone responsive target genes. Menin regulates transcription of cyclin-dependent kinase inhibitor and Hox genes via the chromatin-associated factor LEDGF. Aberrant expression of menin target genes in tumours in MEN1 patients suggests that loss of writing of the H3K4me3 mark contributes to MEN1 tumourigenesis. At present, drugs are being developed that target chromatin modifications. The identification of compounds that could restore H3K4me3 on menin target genes would provide new therapeutic strategies for MEN1 patients.

Medullary thyroid carcinoma and biomarkers: past, present and future.

The clinical management of patients with persistent or recurrent medullary thyroid carcinoma (MTC) is still under debate, because these patients either have a long-term survival, due to an indolent course of the disease, or develop rapidly progressing disease leading to death from distant metastases. At this moment, it cannot be predicted what will happen within most individual cases. Biomarkers, indicators which can be measured objectively, can be helpful in MTC diagnosis, molecular imaging and treatment, and/or identification of MTC progression. Several MTC biomarkers are already implemented in the daily management of MTC patients. More research is being aimed at the improvement of molecular imaging techniques and the development of molecular systemic therapies. Recent discoveries, like the prognostic value of plasma calcitonin and carcino-embryonic antigen doubling-time and the presence of somatic RET mutations in MTC tissue, may be useful tools in clinical decision making in the future. In this review, we provide an overview of different MTC biomarkers and their applications in the clinical management of MTC patients.

Value of diagnostic radioiodine scintigraphy and thyroglobulin measurements after rhTSH injection.

UNLABELLED: Measurements of thyroglobulin (Tg) levels 72 h after administration of recombinant human thyrotropin (rhTSH) are recommended by the manufacturer in the follow-up of patients with differentiated thyroid carcinoma (DTC). In our department, Tg measurements are performed both 24 h and 72 h after administration of rhTSH, together with 72 h post rhTSH 131I whole body scintigraphy (WBS). The OBJECTIVE of this study is to compare the diagnostic usefulness of Tg measurements 24 and 72 h after rhTSH administration, and 131I WBS. PATIENTS AND METHODS: 181 patients were included who had been referred to our Nuclear Medicine Department for follow-up after 131I ablation of DTC. Tg measurements 24 h (Tg24) and 72 h (Tg72) after rhTSH, and 131I WBS, were done in all patients. The lower detection limit of Tg was 0,2 microg/l. RESULTS: 47 patients (26%) had detectable Tg levels: in 4/47 cases (8%) only Tg24 was detectable (always <1 microg/l), and in 6/47 cases (11%), only Tg72 was detectable. In 10/47 patients with detectable Tg-levels, Tg24 and Tg72 tested equally. In 27/47 cases, Tg24 was lower, and in 10/47 higher, than Tg72. Two patients with one or two positive Tg-test results also had a positive 131I WBS. In 8 patients (14%) only the 131I WBS was positive; an anatomical substrate for such a Tg-negative positive WBS was confirmed in only 2 patients. CONCLUSION: Tg-measurement 72 hours after rhTSH injection reveals all clinically relevant detectable Tg-levels. Diagnostic 131I scintigraphy may be omitted, even in high-risk patients.

Frequency of Von Hippel-Lindau germline mutations in classic and non-classic Von Hippel-Lindau disease identified by DNA sequencing, Southern blot analysis and multiplex ligation-dependent probe amplification.

The current clinical diagnosis of Von Hippel-Lindau (VHL) disease demands at least one specific [corrected] VHL manifestation in a patient with familial VHL disease, or, in a [corrected] sporadic patient, at least two or more hemangioblastomas or a single hemangioblastoma in combination with a typical visceral lesion. To evaluate this definition, we studied the frequency of germline VHL mutation in three patients groups: (i) multi-organ involvement (classic VHL), (ii) limited VHL manifestations meeting criteria (non-classic VHL) and (iii) patients with VHL-associated tumors not meeting current diagnostic VHL criteria. In addition, we validated multiplex ligation-dependent probe amplification (MLPA) as a rapid and reliable quantitative method for the identification of germline VHL deletions. The frequency of germline VHL mutations was very high in classic VHL cases with multi-organ involvement (95%), lower in non-classic cases that meet current diagnostic criteria but have limited VHL manifestations or single-organ involvement (24%) and low (3.3%), but tangible in cases not meeting current diagnostic VHL criteria. The detection of germline VHL mutations in patients or families with limited VHL manifestations, or single-organ involvement is relevant for follow-up of probands and early identification of at-risk relatives.

A phase II trial of imatinib therapy for metastatic medullary thyroid carcinoma.

CONTEXT: Medullary thyroid carcinoma (MTC) metastasizes early in its clinical course. No effective systemic therapy is available. Generally (somatic or germline), mutations in the rearranged during transfection gene are considered essential in the pathogenesis of MTC. OBJECTIVE: We investigated imatinib, a tyrosine kinase inhibitor, as a potential treatment in patients with disseminated MTC. DESIGN: A phase II study was initiated using 600 mg imatinib daily with a possible dose increase to 800 mg in case of progression. Standard Response Evaluation Criteria in Solid Tumors were used using computed tomography or magnetic resonance imaging every 2 months. RESULTS: There were 15 patients with disseminated MTC treated for up to 12 months. No objective responses were observed. Four patients had stable disease over 24 months. Three patients stopped treatment due to toxic effects [fatigue (n = 2) and nausea (n = 1)]. In four cases the dose of imatinib was decreased because of toxicity [rash and malaise (n = 2) and laryngeal swelling (n = 2)]. Emergency tracheotomy was performed in two cases due to mucosal swelling of the larynx in patients with recurrent nerve palsy and a narrow vocal cleft. In nine patients with a history of a thyroidectomy, the dose of supplemental thyroid hormone was increased because of serious hypothyroidism. CONCLUSIONS: Imatinib therapy yielded no objective responses and induced considerable toxicity in patients with MTC. A minority of patients had stable disease. Patients with supplemented hypothyroidism or with recurrent nerve palsy are specifically at risk for serious adverse events and need special attention when treated with imatinib.

Counselling in multiple endocrine neoplasia syndromes: from individual experience to general guidelines.

Counselling of patients and closely related family members has to take a central place in management of hereditary diseases, like multiple endocrine neoplasia (MEN) syndromes including von Hippel-Lindau (VHL) disease. In the strategy of health care, preventive medicine such as periodic clinical examination of families at-risk needs a high priority, because in general it is assumed that continuity in attendance is cost-effective. Counselling has to be based on individual medical experience of the doctor, adjusted to common guidelines and the findings in the family. Information leaflets, appropriate outpatient departments and an extensive network of specialists will facilitate continuity in care. Flow diagrams involving practical guidelines for diagnosis, treatment and follow up need to be applicable and after adjustment, should be accepted generally. Specially trained paramedics for counselling are required as a network that will guarantee periodic clinical examination and secure optimal prevention. Such paramedics will coordinate nationwide multidisciplinary guidance, and organize preventive and emergency cure for these patients. They will be supervised by expert clinicians in the field, and collaborate with specialists for social and psychological issues, patient organizations and clinical genetic centres. All of these professionals are responsible together for providing patients with up to date clinical information (via newsletters, Internet, etc.). Recently, in the Netherlands, a project was initiated to guarantee continuity in care and study the delivery of care. In order to realize this plan, funding has to be provided in the current research programme. In a future system support has to be obtained on a continuous base, preferably by the government and health care insurers and supervised by the national institute for health care.

Detection of circulating Tg-mRNA in the follow-up of papillary and follicular thyroid cancer: how useful is it?

To investigate the usefulness of thyroglobulin mRNA (Tg-mRNA) detection in peripheral blood in the follow-up of papillary and follicular (differentiated) thyroid cancer, a literature study was performed. Both evidence for and evidence against the usefulness of Tg-mRNA detection were found. Also, evidence for the expression of Tg-mRNA in cells other than normal or neoplastic thyroid follicular cells was found. It is concluded that currently Tg-mRNA detection is not a useful tool in the follow-up of differentiated thyroid carcinoma, but that the concept of using RT-PCR measurements during follow-up still warrants further research.

Postnatally disturbed pancreatic islet cell distribution in human islet amyloid polypeptide transgenic mice.

OBJECTIVE: Islet amyloid polypeptide (IAPP)/amylin is produced by the pancreatic islet beta-cells, which also produce insulin. To study potential functions of IAPP, we have generated transgenic mice overexpressing human IAPP (hIAPP) in the beta-cells. These mice show a diabetic phenotype when challenged with an oral glucose load. In this study, we examined the islet cytoarchitecture in the hIAPP mice by examining islet cell distribution in the neonatal period, as well as 1, 3 and 6 months after birth. RESULTS: Neonatal transgenic mice exhibited normal islet cell distribution with beta-cells constituting the central islet portion, whereas glucagon and somatostatin-producing cells constituted the peripheral zone. In contrast, in hIAPP transgenic mice at the age of 1 month, the glucagon-immunoreactive (IR) cells were dispersed throughout the islets. Furthermore, at the age of 3 and 6 months, the islet organisation was similarly severely disturbed as at 1 month. Expression of both endogenous mouse IAPP and transgenic hIAPP was clearly higher in 6-month-old mice as compared to newborns, as revealed by mRNA in situ hybridisation. CONCLUSIONS: Mice transgenic for hIAPP have islets with disrupted islet cytoarchitecture in the postnatal period, particularly affecting the distribution of glucagon-IR cells. This islet cellular phenotype of hIAPP transgenic mice is similar to that of other mouse models of experimental diabetes and might contribute to the impaired glucose homeostasis.

Long-term effect of fish oil diet on basal and stimulated plasma glucose and insulin levels in ob/ob mice.

In this study, the ob/ob mouse model was used to investigate epidemiological evidence linking fish intake to relative reduction in incidence of Type 2 diabetes mellitus and glucose. We have investigated, in comparison to low and high fat diets, the effect of a fish oil diet on basal and stimulated plasma glucose and insulin levels in male and female ob/ob mice. Mice were fed for 12 months with a saturated fat diet containing 25% lard, with a low fat diet containing 5% soybean oil, with a polyunsaturated fat diet containing 25% safflower seed oil (n-6) or with polyunsaturated fat diet containing 23% fish oil (n-3). Total body weight increased to approximately 100 g at the end of the experiment, with the highest increase in the order of lard > safflower oil > fish oil > soybean oil diet. Intercurrent deaths were found especially in the fish oil diet group. Compared to the other diet groups, plasma insulin levels of the fish oil diet group were significantly increased 3 months after the start of the diet and remained higher for another 3 months. Thereafter, the level declined to those of the other diet groups. Glucose-tolerance tests at 3, 6, 8 and 10 months showed a tendency of more efficient tissue glucose uptake in the fish oil group compared to the other groups, which was in accordance with a higher plasma insulin levels. At 12 months, microscopy revealed an increased severity of hepatic brown pigment accumulation and extramedullary haematopoiesis in the spleen of mice fed with fish oil. We conclude that fish oil diet in ob/ob mice reduced the body weight gain and increased the glucose-induced insulin secretion. Fish oil diet also increased intercurrent mortality. However, a consistent course of death could not be established using morphological parameters.

Guidelines for diagnosis and therapy of MEN type 1 and type 2.

This is a consensus statement from an international group, mostly of clinical endocrinologists. MEN1 and MEN2 are hereditary cancer syndromes. The commonest tumors secrete PTH or gastrin in MEN1, and calcitonin or catecholamines in MEN2. Management strategies improved after the discoveries of their genes. MEN1 has no clear syndromic variants. Tumor monitoring in MEN1 carriers includes biochemical tests yearly and imaging tests less often. Neck surgery includes subtotal or total parathyroidectomy, parathyroid cryopreservation, and thymectomy. Proton pump inhibitors or somatostatin analogs are the main management for oversecretion of entero-pancreatic hormones, except insulin. The roles for surgery of most entero-pancreatic tumors present several controversies: exclusion of most operations on gastrinomas and indications for surgery on other tumors. Each MEN1 family probably has an inactivating MEN1 germline mutation. Testing for a germline MEN1 mutation gives useful information, but rarely mandates an intervention. The most distinctive MEN2 variants are MEN2A, MEN2B, and familial medullary thyroid cancer (MTC). They vary in aggressiveness of MTC and spectrum of disturbed organs. Mortality in MEN2 is greater from MTC than from pheochromocytoma. Thyroidectomy, during childhood if possible, is the goal in all MEN2 carriers to prevent or cure MTC. Each MEN2 index case probably has an activating germline RET mutation. RET testing has replaced calcitonin testing to diagnose the MEN2 carrier state. The specific RET codon mutation correlates with the MEN2 syndromic variant, the age of onset of MTC, and the aggressiveness of MTC; consequently, that mutation should guide major management decisions, such as whether and when to perform thyroidectomy.

Clinical management of Von Hippel-Lindau (VHL) disease.

Von Hippel-Lindau (VHL) disease is an autosomal, dominant inherited tumour syndrome with an estimated prevalence of 2-3 per 100,000 persons. A germline mutation in the VHL gene predisposes carriers to tumours in multiple organs. These tumours may include haemangioblastoma in the retina and central nervous system (CNS), renal cell carcinoma, phaeochromocytoma, islet cell tumours of the pancreas, and endolymphatic sac tumours, as well as cysts and cystadenoma in the kidney, pancreas, epididymis and broad ligament. Penetrance of VHL disease is high, most carriers of a VHL germline mutation develop one or more tumours by the age of 60 years. The most common symptoms include: loss of vision, raised intracranial pressure, neurological deficits, paroxysmal raised blood pressure and local pain. At present, metastases from renal cell carcinoma and neurological complications from cerebellar haemangioblastoma are the most common causes of death. However, it is anticipated that intensive radiological and clinical monitoring, and advanced operation techniques will reduce both morbidity and mortality in patients with VHL disease.

Molecular genetic aspects of Von Hippel-Lindau (VHL) disease and criteria for DNA analysis in subjects at risk.

Von Hippel-Lindau (VHL) disease is an autosomal, dominantly inherited tumour syndrome. Carriers of a germline mutation in the VHL tumour suppressor gene tumours are predisposed to develop tumours that are multicentric or bilateral, and manifest at a younger age than in situations without a VHL germline mutation. The mutation spectrum is heterogeneous, with mutations scattered throughout most of the VHL gene. Although some recurrent mutations have been reported, most families have their own unique germline mutation. Tested individuals are no longer uncertain regarding their risk for developing the disease and family members who are non-carriers are relieved of the burden of repeated clinical monitoring.VHL germline mutations are identified in virtually all families and sporadic patients with classic VHL disease, but also in patients who do not meet clinical diagnostic criteria. The chance of finding a VHL germline mutation in (apparently) sporadic patients not fulfilling the criteria increases with: young age at diagnosis, the presence of multi-centric or bilateral tumours, involvement of multiple organs and a positive family history of VHL associated tumours.

Medullary thyroid carcinoma: role of genetic testing and calcitonin measurement.

All patients with a thyroid nodule should have their plasma CT measured. Stimulated CT is generally better than basal, but in the lower ranges false negatives and false positives still occur. In families with hereditary MTC, RET gene mutation analysis has superseded measurement of plasma CT in the detection of asymptomatic disease gene carriers. All individuals with apparently sporadic MTC, but in whom there is some suspicion of familial disease, should also have RET genetic analysis. A negative DNA result practically excludes the possibility of hereditary MTC in families where an index case has been investigated and obviates the need for further biochemical evaluation. Disease gene carriers may be divided into three distinct risk groups depending on the specific RET gene mutation in the family. The age at which presymptomatic surgery has to be performed depends on the risk group to which the patient belongs. Compared with the results of DNA analysis, the results of CT stimulation tests have become less important in the assessment of timing of surgery. During follow-up of patients who underwent surgery, measurement of plasma basal CT is still useful. The high sensitivity of measuring stimulated CT levels does not outweigh the burden of life-long periodic stimulation tests and the limited clinical consequences of slightly elevated levels. Stimulation tests are inevitable for persons at risk who prefer not to have genetic testing.

Acute dyspnoea resulting from pulmonary oedema as the first sign of a phaeochromocytoma.

The day after undergoing neck dissection, a 42-year-old woman developed acute dyspnoea due to pulmonary oedema. Measurements with a Swan-Ganz catheter revealed not only cardiac depression but also a greatly increased peripheral vascular resistance: 5,400 dyn x s x cm(-5)/m2. A phaeochromocytoma with acute cardiac failure leading to pulmonary oedema was considered. Treatment with alpha- and beta-blockers was complicated by severe hypotension and later ventricular fibrillation. Mechanical ventilation was required for 6 days following resuscitation. Investigation of the urine subsequently showed greatly increased catecholamine concentrations, while imaging revealed bilateral adrenal tumours. Our case history shows that acute pulmonary oedema may be the presenting manifestation of a phaeochromocytoma. The pulmonary oedema resulted partly from backward failure following tachycardia, myocyte necrosis and the greatly increased peripheral vascular resistance, and partly from increased permeability of the capillary network in the lungs.

Efficacy of high therapeutic doses of iodine-131 in patients with differentiated thyroid cancer and detectable serum thyroglobulin.

Serum thyroglobulin (Tg) is usually the best marker of residual or metastatic disease after treatment of differentiated thyroid cancer. We evaluated the effect of so-called blind therapeutic doses of iodine-131 in patients with detectable Tg during suppressive levothyroxine treatment (Tg-on), and in patients with a negative diagnostic scintigram but detectable Tg during the hypothyroid phase (Tg-off). Twenty-two patients with differentiated thyroid carcinoma underwent total thyroidectomy and radioiodine ablation. During the follow-up, six patients with detectable Tg-on and 16 patients with detectable Tg-off were identified. All patients were treated with a blind therapeutic dose of 7,400 MBq iodine-131. Diagnostic scintigrams were compared with post-treatment scintigrams. Tg-off was measured in 16 cases, 1 year after the administration of the blind therapeutic dose, at the time of the follow-up diagnostic scintigram. Six patients were followed up by Tg-on only. Post-therapy scintigrams revealed previously undiagnosed local recurrence or distant metastases in 13/22 cases (59%); the remaining nine post-therapy scintigrams were negative. At the time of the blind therapeutic doses, Tg-off values ranged from 8 to 608 microg/l. After 1 year of follow-up, Tg-off decreased in 14/16 (88%) patients. In all patients who were followed by Tg-on only (n=6), a decrease in Tg values was measured. It is concluded that blind therapeutic doses resulted in a decrease in Tg levels in the majority of patients with suspected recurrence or metastases. The post-treatment scintigrams revealed pathological uptake in 59% of patients.

[From gene to disease; from the RET gene to multiple endocrine neoplasia types 2A and 2B, sporadic and familial medullary thyroid carcinoma, Hirschsprung disease and papillary thyroid carcinoma]. / Van gen naar ziekte; van het RET-gen naar multipele endocriene neoplasie type 2A en 2B, sporadisch en familiair medullair schildkliercarcinoom, ziekte van Hirschsprung en papillair schildkliercarcinoom.

The RET gene encodes a receptor tyrosine kinase involved in normal and neoplastic development of neural crest cell lineages. Activating RET mutations are present in patients with multiple endocrine neoplasia types 2A and 2B (MEN2A, 2B) and in familial medullary thyroid carcinoma (FMTC) patients, whereas inactivating RET mutations are found in patients with Hirschsprung (HSCR) disease. In particular for MEN2A and FMTC, the clinical management largely depends on the specific mutation found.

[Lump in the neck: 4 patients with a medullary thyroid carcinoma]. / Een knobbeltje in de hals: 4 patiënten met een medullair schildkliercarcinoom.

In a 25-year-old man, medullary thyroid carcinoma (probably a solitary sporadic form) was diagnosed following investigation of a small lump in the patient's neck. This was removed and followed up with further treatment. In a 27-year-old man, episodes of headache, palpitations and excessive perspiration (due to a pheochromocytoma) and a positive family history of thyroid problems led to further investigations and the subsequent diagnosis of multiple endocrine neoplasia (MEN) type 2A. The patient died at 48 years of age as the result of liver metastases. A total thyroidectomy had been carried out on a 19-year-old man with familial medullary thyroid carcinoma. The calcitonin levels remained elevated, but no tumour residues could be found. A 16-year-old girl with MEN type 2B had also previously undergone surgery. Her main complaint consisted of persistent constipation. Thyroid carcinomas usually present as a nodule in the neck. In 25% of cases, medullary thyroid carcinoma is part of the MEN2 syndrome. The clinical approach for medullary thyroid carcinoma is based on pathological findings following fine needle aspiration biopsy. The results of DNA tests determine the course of treatment and the need for family testing. In families with a hereditary form, there is a clear genotype-phenotype correlation. Early diagnosis and treatment can improve life expectancy.

[Islet amyloid and diabetes mellitus type 2]. / Eilandjesamyloïd en diabetes mellitus type 2.

Type 2 diabetes mellitus is a heterogeneous and multifactorial disorder accompanied by severe complications and a reduced life expectancy. Histopathologically, it is characterized by deposition of protein in the islets of Langerhans in the pancreas ('islet amyloid'). The 37 amino acids 'islet amyloid polypeptide' (IAPP) was discovered in 1986 as the building block of islet amyloid. The identification of IAPP caused an intensification of research on islet amyloid. In the past few years, particularly transgenic mouse technology has shown that islet amyloidosis is a consequence as well as an (additional) cause in the pathogenesis of type 2 diabetes. Islet amyloid has turned out to be a pathogenic factor, which is accompanied by death of beta-cells and reduction of the insulin producing capacity. This knowledge offers opportunities for the development of novel (preventive) therapy and thus for a better life expectancy of persons which develop type 2 diabetes.

Parents' responses to disclosure of genetic test results of their children.

The psychological reactions of 22 parental couples and 3 single parents were investigated after disclosure of genetic test results of their children. The children were tested for the early-onset, monogenetic cancer disorder multiple endocrine neoplasia type 2. Participants came from 13 different families and were aged between 28 and 47 years. Parents who were informed that their child was a gene carrier reacted with resignation, showed moderate to high levels of test-related and general anxiety, but few psychological complaints. Daily activities were disturbed in 43% of the parents with carrier-children. There was little disruption of the parents' future perspective, apart from some socioeconomic disadvantages and increased parental concern for the carrier-children. Most parents with carrier-children showed restraint with respect to short-term prophylactic treatment. Parents with favorable test results showed significantly less anxiety and no disturbance in their daily activities. They did not, however, seem to be reassured by the DNA test result. These parents questioned the reliability of the DNA test, wanted confirmation of the test results, and were eager to continue screening of their noncarrier children. Parents, especially those with a lower level of education and/or a pessimistic view of the future, were distressed by unfavorable test results. Additional counseling is advised to prevent parents of carrier-children worrying unnecessarily, or parents with children in whom the disease gene was not found being not reassured. Am. J. Med. Genet. 94:316-323, 2000.