A survey on Prader-Willi syndrome in the Italian population: prevalence of historical and clinical signs.

Clinical criteria for the diagnosis of Prader-Willi Syndrome (PWS) were established by consensus in 1993 (Holm et al.). Specific molecular testing is now available and the purpose of diagnostic criteria has shifted to identify individuals to test, thus avoiding the expense of unnecessary analysis. The aim of this study was to find clinical indicators to select patients with suspected PWS for laboratory testing. We analyzed the prevalence of clinical signs and symptoms in 147 genetically diagnosed Italian patients with PWS (67 males and 80 females), aged from 9 months to 34.6 years (13.6 +/- 8.3 years), using the consensus diagnostic criteria, and according to age, sex and type of genetic abnormality. The prevalence of several clinical features changed significantly with age, but very few with sex. According to genetic subtypes (deletion vs UPD), only hypopigmentation and acromicria were more frequent in patients with deletion. Some criteria considered as minor or supportive by Holm et al. have higher prevalence than some major criteria. In conclusion, in order to identify patients with suspected PWS to submit to laboratory testing, we recommend a classification of clinical criteria according to age, giving more attention to those so-called minor or supportive criteria.

Deletion of the SHOX gene in patients with short stature of unknown cause.

A fluorescence in situ hybridization (FISH) study was performed in 56 patients with short stature of unknown cause in order to establish the role of deletion of the SHOX gene in this population. FISH analysis was carried out on metaphase spreads and interphase lymphocytes from blood smears using a probe specific for the SHOX gene. Deletion of SHOX was found in four patients (7.1%). No skeletal abnormalities were detected in these patients either at the physical examination or at X-rays of the upper and lower limbs. Present results indicate that SHOX plays an important role also in short stature of unknown cause, and FISH analysis appears as an easy, appropriate, and inexpensive method for the detection of SHOX deletion.

A mutation in the pleckstrin homology (PH) domain of the FGD1 gene in an Italian family with faciogenital dysplasia (Aarskog-Scott syndrome).

Aarskog-Scott Syndrome (AAS) is an X-linked disorder characterised by short stature and multiple facial, limb and genital abnormalities. A gene, FGD1, altered in a patient with AAS phenotype, has been identified and found to encode a protein with homology to Rho/Rac guanine nucleotide exchange factors (Rho/Rac GEF). However, since this original report on identification of a mutated FGD1 gene in an AAS patient, no additional mutations in the FGD1 gene have been described. We analysed 13 independent patients with clinical diagnosis of AAS. One patient presented a mutation that results in a nucleotide change in exon 10 of the FGD1 gene (G2559>A) substituting a Gln for Arg in position 610. The mutation was found to segregate with the AAS phenotype in affected males and carrier females in the family of this patient. Interestingly, Arg-610 is located within one of the two pleckstrin homology (PH) domains of the FGD1 gene and it corresponds to a highly conserved residue which has been involved in InsP binding in PH domains of other proteins. The same residue is often mutated in the Bruton's tyrosine kinase (Btk) gene in patients with an X-linked agammaglobulinemia. The Arg610Gln mutation represents the first case of a mutation in the PH domain of the FGD1 gene and additional evidence that mutations in PH domains can be associated to human diseases.

Short arm rearrangements of sex chromosomes with haploinsufficiency of the SHOX gene are associated with Leri-Weill dyschondrosteosis.

Twelve patients with different features of Turner syndrome, and with Xp and Yp rearrangements involving the pseudoautosomal region (PAR1) are described. In all patients, FISH analysis showed loss of one copy of the Short Stature Homeobox (SHOX)-containing gene. Ten patients had short stature and one disproportionate (mesomelic) normal stature, while the last one had normal stature. Skeletal abnormalities, including shortened ulna, were detected in nine subjects, and in six of them Madelung deformity was observed. These clinical data indicated a genotype phenotype correlation between haploinsufficiency of SHOX, and short stature and skeletal abnormalities.

Retinal degeneration associated with ectopia lentis.

Two brothers had retinal degeneration, lens subluxation, and myopia since early life. There was no evidence of Marfan syndrome, homocystinuria, or other systemic disease. They had nystagmus, myopia, inferior dislocation of the lens, and posterior subcapsular opacities in both eyes. Fundus examination showed attenuated retinal vessels, macular atrophy with occasional pigment accumulation as clumps, and perivascular sleeves. Electroretinography revealed decreased photopic and scotopic responses. The visual fields were constricted. We believe this to be the first report of retinal degeneration with bilateral lens subluxation in a family. It appears to be inherited in an autosomal recessive fashion.

Autosomal recessive familial exudative vitreoretinopathy: evidence for genetic heterogeneity.

Two unrelated families with familial exudative vitreoretinopathy (FEVR) show apparent autosomal recessive inheritance rather than the previously reported autosomal dominant or X-linked recessive mode of inheritance. Compared with the other modes of inheritance, the inherited clinical features here include earlier onset (at birth) and a more severe progressive course.

The gene for mesomelic dysplasia Kantaputra type is mapped to chromosome 2q24-q32.

Mesomelic dysplasia Kantaputra type (MDK) (MIM *156232) is a new autosomal dominant skeletal dysplasia characterized by dwarfism, shortening of the forearms/lower-legs, carpal/tarsal synostosis, and dorsolateral foot deviation. We studied a Thai family in which 15 members in 3 generations were affected with MDK. With reference to the breakpoints of a balanced translocation [t(2;8)(q31;p21)] in patients from a previously reported Italian family with a skeletal dysplasia that appears similar to MDK, a linkage analysis was performed in the Thai family using 50 CA-repeat markers mapped to nearby regions (2q22-q34 and 8p24-p21) of the translocation breakpoints. The results clearly ruled out a linkage of MDK to marker loci at the 8p24-p21 region, whereas all nine affected members available for the study shared a haplotype at four loci (D2S2284, D2S326, D2S2188, and D2S2314) spanning about 22.7 cM in the 2q24-q32 region. The computer-assisted two-point linkage analysis revealed maximum logarithm of odds (lod) scores of 4.82, 4.21, 4.82, and 4.21 (theta = 0) at these loci, respectively. These data indicated that the MDK locus is in the vicinity of D2S2284 and D2S2188 loci that are most likely mapped to 2q24-q32.

Pituitary deficiency and lack of gonads in an XY pseudohermaphrodite with beta 39/lepore haemoglobinopathy.

We describe the occurrence of hypothyroidism and hypogonadotropic hypogonadism in an XY pseudohermaphrodite subject affected by beta-thalassemia. The patient, reared as female, diagnosed at 14 months of age as having a beta 39/Lepore hemoglobinopathy, treated with multiple transfusion therapy, was referred at age of 15 years because of delayed puberty. Complete endocrine evaluation showed low levels, both basal and after combined LHRH-TRH and hCG stimuli, of FSH, LH, TSH, estradiol (E2), testosterone (T), progesterone (P), androstenedione (A), and FT4 levels, and normal PRL, cortisol, 17OHP and ACTH levels. Imaging studies (ultrasound, magnetic resonance, radioisotope scanning and gonadal vessels phlebography) did not show internal genitalia and gonads. Karyotype resulted 46,XY. PCR amplification of the SRY gene confirmed the presence of the Y chromosome. Female genitalia without uterus in a subject with Y chromosome SRY gene, and no detectable testes indicate a condition of male pseudohermaphroditism associated with testicular regression. Low gonadotropin and sex steroid levels are suggestive of combined acquired hypothalamic-pituitary and gonadal impairment, due to iron deposition in both organs. We cannot exclude congenital failure of testosterone synthesis and action in this case, because lack of gonads is an unusual finding in thalassemic hypogonadic subjects.

Phenotypic variability in the chromosome 9 ring.

The syndrome associated to the 9 ring is not commonly observed. The first remark was by Kistenmacher (1970) who examined a male. Later observation of other cases has allowed the syndrome to be described, so that it can be said to be characterized by constant signs, such as microcephaly, psychomotor retardation of varying entity and facial dysmorphism corresponding to that observed in 9 p monosomy. The variability of the phenotype has to be compared with the entity of the telomeric deletion, since the clinical outlook, especially the entity of retardation, could be less serious in case of small deletions.

Spondyloepiphyseal dysplasia tarda and nephrotic syndrome in three siblings.

The association of a spondyloepiphyseal dysplasia tarda (SED-T) with the nephrotic syndrome (NS) was found in three siblings. They have counsaguineous (first cousins) healthy parents. Patient 1 was a boy who was admitted to hospital for oedema at the age of 8 years; NS was diagnosed, renal biopsy revealed mesangioproliferative glomerulonephritis. After 4 years he developed end-stage renal failure and died whilst on haemodialysis. Combined therapy with cyclophosphamide and prednisone was of no benefit. At the age of 11 years his height was 122 cm (< 3rd percentile -3.2 SD); he had a short neck, broad and prominent chest and a short wide trunk. Patient 2, another male, had non-nephrotic proteinuria in a 24-h urinary sample at the age of 11 years; this was confirmed in a later analysis; mild lymphopenia and a reduction of helper T cell (OKT4)/suppressor T cell (OKT8) ratio was also detected. At 22 years of age he was admitted to hospital with end-stage renal failure. He was on haemodialysis for a few months until his mother donated a kidney. At the age of 22 years his height was 157 cm (< 3rd percentile), he had a short trunk with the thoracic cage increased in anteroposterior diameter and shoulder elevation. Roentgenograms revealed a disostosis of the spinal column and pelvis and a slight lombar platyspondylia. Patient 3, a girl, was admitted to hospital at 12.5 years for pain and restricted mobility of the right hip. X-rays showed deep acetabula and short femoral necks and mild dysplastic changes, especially in the right hip.(ABSTRACT TRUNCATED AT 250 WORDS)

Seckel syndrome: report of three sibships with the type I primordial dwarfism. Possible linkage with HLA locus.

The authors report on five cases of Seckel syndrome type I primordial dwarfism, belonging to three unrelated sibships. Immunological and cytogenetic investigations with DEB test did not evidence immunodeficiency or chromosomal fragility. HLA phenotype studies revealed an identical haplotype in affected sibs: a possible linkage with HLA is therefore suggested. Cranial magnetic resonance was performed in three patients and did not evidence any anomaly. One affected female showed precocious puberty at 7 years of age.

Multiple skeletal familial abnormalities associated with balanced reciprocal translocation 2;8(q32;p13).

A father and three of his offspring had skeletal abnormalities consisting of a short forearm, cubitus valgus, fusion of first and second cervical vertebrae, and cleft of L5 and S1. All four had a reciprocal, apparently balanced, translocation 2;8(q32;p13). Normal sibs had normal chromosomes. We conclude that this may be a rare instance of an autosomal dominant condition associated with a balanced chromosome translocation.

Clinical features of monosomy 10qter.

The authors report a 10qter deletion in a 16-month-old boy. The patient's phenotype includes: low birth weight, mental and growth retardation, triangular facies, hypertelorism, prominent nasal bridge, malformed and low set ears, cryptorchidism. The karyotype was 46,XY,del(10)(q26.1 leads to qter). Cytogenetic analysis of both parents, including a search for the fragile site in the 10q25 region, were normal. The assignment of the human GOT structural gene to the 10q25.3 band is suggested.

[Severe mental retardation and slight dysmorphism in a child with a bisatellite extrachromosome: inversion duplication (15)?]. / Grave ritardo mentale e lieve dismorfismo in bambino con extracromosoma bisatellite: inv dup (15)?

A de novo tetrasomy 15 has been reported, in a 6 years old child. The patient had severe mental retardation an minimal physical stigmata, consisting in slight skeletal and facial dismorphism. Cytogenetic analysis showed that extrachromosome, G-like long, was bisatellited and dicentric and was interpreted either as an inversion duplication 15 or as 15; G or D translocation.

[Aarskog's syndrome (facial-digital-genital syndrome). Study of a family (author's transl)]. / Sindrome di Aarskog (sindrome facio-digito-genitale). Studio di una famiglia.

A case of Aarskog syndrome in a 6-years old boy is reported. The patient showed clinical pictures typical of the syndrome: characteristic dysmorphic facies, palpebral ptosis, brachyfalangism, abnormality of the scrotum. Minimal stigmata and clinodactyly of 5th finger were present in a sister. Isolated bilateral clinodactyly was found in other 4 members of the family. The significance of this sign in the context of the syndrome has been discussed. Unusual dermatoglyphic patterns were present in the proband, mother and sister.