[Hereditary progressive arthro-ophthalmopathy (Stickler syndrome)]

The hereditary arthro-ophthalmopathy (Stickler-Syndrome) is a relatively frequent dominantly inherited disorder of connective tissue. The main symptom is strong congenital myopia, which develops often to blindness. On the other hand there is a dysplasia of the meta- and diaphysis of the tubular bones, which varies in form and expression. Within difficulties with differential diagnosis to near syndromes it is important to get a clear diagnosis by ophthalmologic, radiologic and family investigations. Within three members of a family the orthopaedic symptomatology is shown. In case of Stickler-Syndrome surgery in the skeleton system should be prevented.

Myopia and plasma cortisol

Estimation of plasma cortisol by fluorometric technique desorbed by Mallingly's was carried out in 56 cases, including 38 cases of myopia (19 cases of simple myopia and 19 cases of degenerative myopia) and 18 normal individuals. Urinary 17-keto steroids/24 hours was also estimated by Zimmermann technique in 12 out of the 56 cases, which include 8 cases of myopia (4 cases of simple myopia and 4 cases of degenerative myopia) and 4 normal individuals as control. Plasma cortisol level is lower in simple and degenerative myopia than in normal subjects, but on statistical analysis the difference was not of much significance. Patients with simple myopia with positive family history showed lower value of plasma cortisol than patients with simple myopia with negative family history, the difference was also statistically insignificant (P-0.1). In degenerative myopia patients, with and without family history, there was very little difference in plasma cortisol level and statistically highly insignificant (P-0.8). Urinary 17 keto steroid/24 hour values are lower in simple and degenerative myopia than in normal subjects.

[Concordance for myopia and discordance for optic disk cupping in a pair of monozygotic twins]

Of a pair of monozygotic twins who are both myopic, only twin B has an optic nerve pit in her left eye. At the age of 19 her visual acuity was reduced due to macular edema. Three years later, krypton laser coagulation treatment produced an appreciable improvement. Although both twins are myopic, the anisomyopia observed illustrates the influence of environment on ocular refraction.

Selected review on genetic factors in myopia

This article reviews representative literature concerning pedigrees for myopia, heritability studies on refractive error and the ocular components, and other work relating to genetic factors in myopia development. Low myopia most likely reflects the influences of multiple genes. Some types of high myopia may have monogenic inheritance. Refractive error and the ocular refractive components have heritabilities intermediate between zero and one, as complied from several studies, indicating familial resemblance, but also non-genetic variation. It is likely that both heredity and environment have roles in determining refractive status. An understanding of their respective roles awaits the elucidation of the cellular and anatomical mechanisms of myopia development.

Myopia and intelligence: a pleiotropic relationship?

The well-established association between myopia and superior intelligence in the general population was investigated in a group of intellectually gifted children and their less gifted full siblings to determine whether the relationship of myopia to psychometric intelligence is consistent with the hypothesis of pleiotropy, i.e., both characteristics are affected by the same gene or set of genes. Failure to find a difference in degree of myopia, assessed as a metric variable, between intellectually gifted and nongifted siblings would contradict pleiotropy. A variety of possible causal pathways, both genetic and environmental, have been hypothesized in the literature to explain the relationship between intelligence and myopia, and these still cannot be ruled out. It is theoretically noteworthy, however, in view of the independent evidence for the considerable heritability of both intelligence and myopia, that the highly significant gifted-nongifted sibling difference in myopia found in the present study is consistent with the hypothesis that intelligence and myopia are related pleiotropically.

Asymmetric Marfan syndrome

We describe a girl with Marfan syndrome in whom the clinical expression of the disease was much more evident on the left side of the body.

X-linked myopia in Danish family

X-linked infantile myopia is described in a family of 273 members of whom 87 were examined in the National Eye Clinic. The disease may represent a new ocular syndrome, constituted by myopia combined with astigmatism, impaired vision, hypoplasia of the optic nerve heads, and deuteranopia. Obligate carriers presented slight retinal changes. Linkage studies are in progress.

[Association of Recklinghausen's disease, dental dystrophy and myopia in a Tunisian family]

The authors describe a tunisian family including ten patients with neurofibromatosis. Four case reports present dental anomalies (amelogenesis imperfecta) and three have myopia. The authors believe there is no clinical or genetical relation between neurofibromatosis and this dental dystrophia; but myopia may be a clinical expression of Recklinghausen disease.

Heritability estimate for refractive errors--a population-based sample of adult twins

The population-based Finnish Twin Cohort study was used to establish a heritability estimate for refractive errors especially for myopia. The twin cohort was derived from adult same-sexed twins in Finland. The total number of twins with both members alive in 1984 was 23,570. Of these, 3,676 twin pairs were monozygotic, and 8,109 pairs dizygotic. The sample for the present study was linked from the Finnish Police Force data base in 1984, where information of a person's possession of a driver's license and the obligation to wear glasses for far correction when driving a motor vehicle is recorded. Correlations in liability were estimated according to a multifactorial method of Smith. Falconer's heritability was 0.62 among males and 0.98 among females in the age group 28-29 years. When compared to previous twin studies of myopia, the proband concordance rates were higher for both MZ and DZ twin pairs.

[Marshall syndrome. 2 new cases]

Two new familial cases of Marshall syndrome are reported. The main features of this rare syndrome are outlined. Its possible relationship with Stickler syndrome is discussed.

Twin study on myopia

In order to reassess the relative importance of genetic and environmental factors in the development of myopia in Chinese schoolchildren, 90 pairs of MZ and 36 pairs of like-sex DZ twins were enrolled for detailed ophthalmological examination about their ocular refractions. Corneal curvatures and axial lengths were also measured. With equivalent settings of the range for concordance, corneal curvatures showed higher concordance rate (84%) than ocular refractions (65%) and axial lengths (59%) in MZ twins. F-test on the intrapair variances between MZ and DZ twins revealed a significant hereditary role in determining the ocular refraction and its optical components. The degree of genetic determination was expressed by heritability indices, which were derived from intraclass correlation coefficients. The diversity of sample ages and refractions, while making the obtained data difficult to further explore the gene-environment interaction, led to the observation of more intrapair differences with age and myopic progression in MZ twins.

Epiphyseal dysplasia of the femoral head, mild vertebral abnormality, myopia, and sensorineural deafness: report of a pedigree with autosomal dominant inheritance

A family is presented with short stature, femoral epiphyseal dysplasia, mild vertebral changes, and sensorineural deafness inherited as an autosomal dominant trait. Myopia and retinal detachment presenting in adult life were also present in some affected members. We suggest that this disorder may be a distinct entity within the spondyloepiphyseal dysplasia group of disorders.

Stickler's syndrome: a study of 12 families

Stickler's syndrome is a congenital disease of connective tissue with considerable ocular and non-ocular lesions. This study reports 12 pedigrees (10 families and two isolated cases) and evaluates some peculiar ocular aspects not previously reported in the syndrome.

Holt-Oram syndrome with high myopia. A hitherto unreported association in a Chinese patient

One member of a Chinese family with Holt-Oram syndrome also had high myopia, which is a hitherto unreported feature. The genetic background of this unusual association is discussed.

A postaxial polydactyly and progressive myopia syndrome of autosomal dominant origin

A new "postaxial polydactyly-progressive myopia" syndrome of autosomal dominant inheritance is delineated on the basis of nine affected persons in four generations of one family.

Autosomally inherited recessive spastic ataxia, macular corneal dystrophy, congenital cataracts, myopia and vertically oval temporally tilted discs. Report of a Bedouin family--a new syndrome

A Bedouin family is described with an unusual form of spinocerebellar degeneration. Spastic ataxia was found to be associated with congenital cataracts, macular corneal dystrophy and non-axial myopia, in the absence of retardation of somatic or mental maturation. Immunological abnormalities were common. Genetic analysis revealed that the pedigree is expressing the transmission and segregation of a single mutant autosomal recessive gene.

Snowflake degeneration: an independent entity or a variant of retinitis pigmentosa?

We examined eight members of three generations of a family with a history of hereditary retinal degenerative disease. Four affected members have multiple whitish retinal dots resembling snowflakes. Other positive ocular findings in the four members with retinal flakes include myopia, cataract, fibrillary vitreous degeneration with occasional strands, attenuated retinal arterioles, sheathed retinal vessels, occlusion of small retinal vessels, white with and without pressure, annular macular pigment defects, and occasional spicules of pigment. Goldmann perimetry showed irregular annular scotomas in three patients. Electroretinographic response was extinguished in one and subnormal in three. Electro-oculography showed the light rise-to-dark trough ratio to be decreased in the affected patients. Based on results of vitreoretinal biomicroscopy, Goldmann perimetry, and visual electrodiagnostic testing, we suspect that snowflake degeneration may be just a variant of retinitis pigmentosa.

Hereditary cases of congenital microcoria and goniodysgenesis

Presented here are hereditary cases of congenital microcoria associated with goniodysgenesis. The proband was a 64 year-old woman with poor development of collarettes and crypts of the iris. Gonioscopic examination revealed anterior chamber irregularities. Three out of six of her siblings suffered from the same anterior chamber anomaly but did not have glaucoma. All the affected members had microcoria associated with goniodysgenesis which was transmitted in an autosomal dominant pattern.

Colobomatous macrophthalmia with microcornea

The ocular malformation of microcornea, uveal coloboma, high myopia, posterior staphyloma, and macrophthalmia was studied in a family. Clinical characteristics and ocular parameters, including refractive error and axial length, are summarized. The pedigree is consistent with autosomal dominant inheritance of the disorder; expressivity is variable. This unique malformation is differentiated from other well-recognized syndromes of colobomatous microphthalmia.

Familial sinus node disease and degenerative myopia--a new hereditary syndrome?

A family is reported in which the father and both offspring suffered from sick sinus syndrome (SSS) accompanied by degenerative myopia in the two elder of the three family members. In all three individuals, the basic manifestations of the SSS were total sinus arrest with secondary AV junctional rhythm at a normal rate. Only the 7-year-old boy also exhibited paroxysmal atrial flutter and ventricular asystole lasting up to almost 7 s. Since he had, furthermore, recently sustained a left hemiparesis, a ventricular demand pacemaker was implanted. Chronic atrial fibrillation was eventually established in the father in whom observations were available for 16 years. Myopia of -11 D and -4.5 D, respectively, existed in the father and his 14-year-old daughter. The familial association of this defect with SSS suggests a hitherto undescribed genetic syndrome, presumably with underlying autosomal dominant transmission of the two traits.