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Two patients with trisomy for 18p and the proximal segment of 18q (trisomy 18q-) are reported and compared with similar cases from the literature. The phenotype of trisomy 18q- resembles that of full trisomy 18 but differs mainly in the birdlike face, small mouth, more pronounced microretrognathia, minor skeletal dysplasia and inner organ malformations, and less sever vital prognosis.

Speciation and carcinogenesis result from genomic instability at the gametic or at the somatic levels. After an infinity of trials they occur, by chromosome rearrangements, in single individuals or in single cells and evolve by similar chromosomal or clonal evolutions. Loss of heterozygosity for the first event is essential in both processes: in evolution, a chromosomal rearrangement, a pericentric inversion or a Robertsonian fusion, must become homozygous to ensure a reproductive barrier for a new species; Knudson's two-event sequence is a similar situation in cancer. Position effect is equally important: we have shown overexpression of the SOD1 gene in the orangutan phylum probably by an intrachromosomal rearrangement; the t(9;22) in CML acts by typical position effect. Parental imprinting underlies the evolution of genome function and the unset of certain cancers. Evolution and malignancy are interweaved by viruses and oncogenes since the dawn of life. Cancer uses its intelligence to expand and to destroy the other tissues, using subtle metabolic pathways and a variety of tricks to metastasize other cells. It always wins but saws the branch on which it sits. Mankind also grows exponentially, killing thousands of other species, poisoning the oceans and soft waters, polluting the atmosphere, all for his egoistic needs. Man also travels and metastasizes other Earths. He modifies his genome or that of other species, and develops new technologies for his reproduction. He can destroy the planet in an eyeblink. To be or not to be the malignant primate, that will be the dilemma for the 21st Century.

Forty-percent of retinoblastomas are due to a mutation inherited as an autosomal dominant trait with a high penetrance. Cytogenetic forms of retinoblastoma have led to the location of the gene, to the identification of numerous chromosome 13 specific DNA polymorphisms, and to the cloning of the gene. Intragenic DNA polymorphisms are now known. Using Southern blot hybridization, study of the mutation is possible either by direct analysis or by an indirect approach using linkage with polymorphic genetic markers. The majority of cases cannot be examined by these techniques. Their value and limits are discussed.

The availability of more and more reliable obstetrical echographies makes now possible to screen fetuses for microphtalmies and anophtalmies. More over, by mean of linkage studies with DNA markers within a family, we can identify the women who will transmit X-linked diseases, and realize a prenatal diagnosis. This technology can be applied to the following ophthalmological diseases: the X-linked retinoschisis, the choroideremia, the ocular albinism, the Noorie disease, and recently the retinoblastoma. From now on, the use of such a technology which makes it possible to detect ophthalmological diseases in the fetuses, is posing ethical problems especially in case of diseases without any survival prognosis involvement.

The development of cytogenetic high resolution banding techniques has allowed the observation of specific chromosome rearrangements--i.e. microdeletions, translocations--in patients with morbid conditions suspected to have a genetic component but for which a precise etiology had not, or rarely, been recognized. The most striking examples are retinoblastoma, the WAGR complex, Beckwith-Wiedemann syndrome, Langer-Giedion syndrome, Prader-Willi syndrome, Miller-Dieker syndrome and others, which thus could be mapped to the genome. Molecular technology further allowed in a number of cases cloning of the genes proper or of linked DNA polymorphisms permitting genetic counseling.

Chromosome abnormalities represent the major cause of pre- and post-implantation embryo wastage. Indeed, 29% of embryos produced by in-vitro fertilization have an abnormal karyotype. Parthenogenesis (1.6% of the cases) and triploidy (6.4%) are the only abnormalities detectable 17 h after insemination. A total of 23% of activated oocytes with a single pronucleus (1 PN) and 18% of fertilized eggs with three pronuclei (three PN) remained uncleaved, compared with 4% for diploid eggs. The rate of cleavage for parthenogenes is not different from normal eggs. On the contrary, we observed that 29% of three PN-eggs reached the 5- to 8-cell stage 42 h after insemination when compared to 15% for diploids mainly due to a direct division of 56% of three PN-eggs in three cells. A model of development for triploid eggs is proposed, taking into account physiological and cytogenetic observations. The quality of embryos expressed in terms of morphology did not show any difference between embryos proceeding from parthenogenes or diploid eggs. On the contrary, the rate of fragmentation is decreased for triploid (3%) compared with diploid (13%) or activated (17%) embryos. Embryos resulting from one, two, three or four pronucleate ova display different developmental capacities during 5 days' culture in vitro.

Eight primary man-mouse (C11D/TK-) hybrids, twenty three primary and seven secondary man-hamster (CH/HGPRT-) were analyzed for human phosphoglycolate phosphatase (PGP) and for human chromosomes. The following results were obtained: 1. A positive correlation is observed between the chromosome 16 and PGP. 15 hybrids are chr.16+PGP+, 14 hybrids are chr.16-PGP- and 4 hybrids are chr.16-PGP+. 2. The percentage of dissociation between PGP and the chr.16 is low (12%) in comparison with the high percentage of dissociation between PGP and the other autosomes (between 37% and 65%). 3. Excepted the chromosome 16, the other autosomes are observed in hybrids PGP-. These different results indicate the localization of the gene for human PGP on the chromosome 16. The dissociation results chr.16-PGP+ are explained by the breakage of the chr.16 in the hybrids.

Two patients with typical Langer-Giedion or trichorhino-phalangeal type II syndrome are reported. One had an apparently normal karyotype. The second had an intercalary del 8q23. Attention is drawn to the severe bone defects seen in the latter and observations from the literature are discussed. The critical segment is assigned to band 8q23. The syndrome may result in a number of cases from a visible deletion, and in other instances from a more conventional gene mutation, although the molecular mechanism is uncertain.

A total 23 enzymatic markers were analyzed in cell hybrids obtained between Cebus capucinus (CCA) fibroblasts and a Chinese hamster cell line. The following markers, or syntenic groups, could be localized in CCA chromosomes homologous to human chromosomes or chromosome segments: PGD-ENOl-PGMl, MDH1, IDH1, PGM2, PGM3-ME1, AK3, TPI-LDHB-PEPB, GPI, and SODl. The following syntenic groups were observed but could not be localized: GUK1-FH and MPI-PKM2. The following loci could not be localized with full confidence: LDHA, NP, PEPD, ITP, and PGK.

Nineteen cell hybrids were obtained by fusing rabbit (Oryctolagus cuniculus, OCU) fibroblasts and a Chinese hamster cell line HGPRT. Eleven enzymatic markers were investigated for cosegregation analysis. Seven could be assigned to OCU chromosomes: LDHA to OCU1; LDHB and TPI to OCU4; PEPB, NP, and ITP to OCU16; and G6PD to OCUX. Two assignments were considered possible: MDH2 to OCU15, and GUK to OCU3 or 15. Two could not be assigned: MDH1 and PGD. These results are consistent with the OCU-HSA chromosome homocologies previously reported, except for PEPB.

Three 45,X males have been studied with Y-DNA probes by Southern blotting and in situ hybridization. Southern blotting studies with a panel of mapped Y-DNA probes showed that in all three individuals contiguous portions of the Y chromosome including all of the short arm, the centromere, and part of the euchromatic portion of the long arm were present. The breakpoint was different in each case. The individual with the largest portion (intervals 1-6) is a fertile male belonging to a family in which the translocation is inherited in four generations. The second adult patient, who has intervals 1-5, is an azoospermic, sterile male. These phenotypic findings suggest the existence of a gene involved in spermatogenesis in interval 6 in distal Yq11. The third case, a boy with penoscrotal hypospadias, has intervals 1-4B. In situ hybridization with the pseudoautosomal probe pDP230 and the Y chromosome specific probe pDP105 showed that Y-derived DNA was translocated onto the short arm of a chromosome 15, 14, and 14, respectively. One of the patients was a mosaic for the 14p+ translocation chromosome. Our data and those reported by others suggest the following conclusions based on molecular studies in eight 45,X males: The predominant aetiological factor is Y;autosome translocation observed in seven of the eight cases. As the remaining case was a low-grade mosaic involving a normal Y chromosome, the maleness in all cases was due to the effect of the testis determining factor, TDF. There is preferential involvement of the short arm of an acrocentric chromosome (five out of seven translocations) but other autosomal regions can also be involved. The reason why one of the derivative translocation chromosomes becomes lost may be that it has no centromere.

A phenotypically normal 32-year-old male with azoospermia was found to have a 45,X karyotype with presence of excess euchromatic material on 14p. The parent's karyotypes are normal. This observation is interpreted as a Y/14 translocation with loss of the heterochromatic Y chromosome material.

The karyotype of Microcebus murinus (MIM) (Lemuridae) is considered by Dutrillaux (1979) as the closest to the karyotype ancestral to all primates. A large number of homoeologies exists between the banding patterns of MIM chromosomes and those of man (HSA). We report a comparison of the gene maps of these two species which confirms most of these homoeologies. Fifteen cell hybrids were obtained by fusing MIM fibroblasts and an HPRT- Chinese hamster cell line. Twenty-seven enzyme markers were investigated. The following assignments were demonstrated: NP to chromosome MIM 2, homoeologous to HSA 14; the syntenic group PGD—ENOl—PGMl to MIM 3, homoeologous to HSA lp; LDHA to MIM 5, homoeologous to HSA 11; ME1 to MIM 6, homoeologous to HSA 6; the syntenic group LDHB—CS—PEPB—EN02—TPI to MIM 7, homoeologous to HSA 12; the syntenic group AK1—AK3 to MIM 10, which we considered to be homoeologous to HSA 9 (we do not consider MIM 9 to be homoeologous to HSA 9, as does Dutrillaux, 1979); GOT1 to MIM 15, homoeologous to HSA 10; the syntenic group HPRT—G6PD—PGK—GLA to MIM X. Synteny dissociation in three hybrids suggests closer linkage between G6PD and HPRT than between PGK—GLA and HPRT. Three syntenic groups, known in man, were confirmed in MIM but could not be assigned with full confidence: ACPI—MDH1 , MPI—PKM2, andPEPD—GPL GUK1 and PEPC, known to be syntenic in man, were found to be asyntenic in MIM and could not be assigned. PGM2 and SOD1 could not be assigned. A comparison of these gene assignments with those known in Cebus capucinus showed a remarkable homoeology for six chromosomes of the two species.

Fifty-five oocytes recovered in an in-vitro fertilization (IVF) programme and remaining unfertilized when observed 42 h after insemination were prepared for chromosomal analysis. Sixteen oocytes displayed no polar body at the time of fixation and were supposed to be in metaphase I. In fact only two of them were in diakinesis, the others containing a diploid set of metaphase II chromosomes indicating that in 89% of the cases oocytes achieved meiosis without any extrusion of the first polar body. Thirty-nine oocytes in metaphase II were analysed. Nine were abnormal showing three D nullosomies, one G disomy, one double disomy for a 3 and a D chromosome, one deletion of the long arm of a G chromosome, one cell with extra chromosomes and/or chromosome breaks, one endoreduplication and one tetraploidy. The overall rate of abnormalities reached 22%. This high rate of chromosome anomalies can be explained by the nature of this population of fertilization failure, the frequently advanced maternal age and the use of superovulation treatments.

Quantitative red cell adenylate kinase (AK-1) assay has been used in 8 patients with partial duplication or deletion of chromosome 9 in an attempt to find the precise intrachromosomal location of the structural gene locus. All regions of chromosome 9 are represented in abnormal dosage in at least one patient. A 43% increase in AK-1 activity was found to be associated with duplication of the terminal band of the long arm of chromosome 9. Duplication of all other parts of chromosome 9 were associated with normal enzyme activity. These findings not only confirm the assignment of the AK-1 locus to chromosome 9 made previously in somatic cell hybrids, but suggest a more precise assignment to region 9q33 leads to qter. This places the ABO:Np-1:AK-1 linkage group at the distal end of the long arm of chromosome 9.

A patient with the phenotype of trisomy 21 (Down syndrome) was found to have a normal karyotype in blood lymphocytes and fibroblasts. Assessment of the chromosome 21 markers SOD1, CBS, ETS2, D21S11, and BCEI showed partial trisomy by duplication of a chromosome segment carrying the SOD1, CBS, and ETS2 loci and flanked by the BCEI and D21S11 loci, which are not duplicated. This submicroscopic duplication at the interface of 21q21 and 21q22.1 reduces to about 2000-3000 kb the critical segment the trisomy of which is responsible for the phenotype of trisomy 21.

The improvement of chromosome banding techniques has much increased the frequency of detected forms of retinoblastoma. Ten rearrangements involving 13q14 were observed in a series of 105 retinoblastoma patients including: five de novo deletions, one of them with suspected mosaicism; one de novo apparently balanced translocation; four deletions due to three familial insertions. Such a mechanism could account for pedigrees showing transmission of the tumor through unaffected carriers. Apparently unrelated rearrangements were also observed. Clinical aspects of these constitutional rearrangements are briefly discussed. Comparison with the literature data is presented.

An 11-year-old girl with 10q26qter deletion is described and compared with another patient reported in the literature. The most characteristic features of monosomy 10qter seem to be: severe mental retardation; growth retardation; microcephaly; and facial dysmorphism with a long and triangular facies, a broad and prominent nasal bridge, a poorly developed tip of the nose, a short philtrum, and flattened angles of the mandible. Several of these features are opposed in type and countertype to features of trisomy 10qter.

A 20-month-old male patient was referred because of severe growth and mental retardation, bilateral glaucoma, hypospadias, and cryptorchidism. Karyotyping revealed a de novo complex three-chromosome rearrangement as well as deletion of band 11p13:46,XY,t(4;7;15)(q212;p14;q26),del(11) (p13p14). Trabeculectomia revealed bilateral aniridia. Surgery on the genitalia revealed male pseudohermaphroditism and bilateral gonadoblastoma. The kidneys were normal. A deficiency in catalase (CAT) activity allowed the regional assignment of the CAT gene to band 11p13.

We have previously mapped the gene coding for catalase to 11p13 by gene dosage analysis. Deletion of this chromosomal region causes aniridia, mental retardation, and predisposition to Wilms' tumor (WT). In the present study, 22 patients with various etiologic forms of WT and/or aniridia were investigated. The catalase (CAT) level and karyotype were examined in order to determine the linkage and the gene ordering on chromosome #11 of the different loci involved. The CAT concentration was normal in the 19 cases without detectable chromosomal abnormalities.

A cytogenetic investigation of 110 adult baboons (Papio cynocephalus) captured in Kenya and sacrificed at the Institut Pasteur, Paris, showed the absence of anomalies, numerical or structural bearing on nonheterochromatic material; a polymorphism of the AgNOR-positive secondary constriction of chromosome 5 in 12% of the animals; a polymorphism of a secondary constriction of chromosome 7 in 2% of the animals; a fragile site of chromosome 6 in one animal. We believe that our data show that cytogenetic observations in present day primates probably reflect their chromosomal evolution.

Summary A family with monozygotic twins is reported in which the propositus, one of the twins, was discovered, on the occasion of routine blood typing, to have a mixture of 50 % D+ ( dce/DcE ) and 50 % D — ( dce/dcE ) red blood cells. The two populations of cells, when separated, did not differ in any of the 19 marker systems investigated. The probability for the twins to be monozygotic was 0.9999. Through the study of 26 genetic marker systems, paternity could also be proved beyond all reasonable doubt with a probability of 0.999. However, both twins had the dcE haplotype while the mother was dce/dce and the father DCe/DcE , the latter genotype being based on a significant double dose D curve obtained by agglutination kinetic assays. Two hypothesis of mutation are discussed : 1o A somatic mutation in one of the cells following the first post-zygotic mitosis. In this cell the paternal Rh complex is supposed to mutate from DcE to dcE . 2o A half chromatid mutation in the paternal gamete giving rise, following one post-zygotic meioses, to 2 daughter cells, one dce/DcE and one dce/dcE . Two mechanisms may be put forward to explain the Rh mosaicism in the propositus. 1. The cleavage for the twin formation occurs after the first post-zygotic mitosis, each daughter cell giving rise to one twin, and the Rh mosaicism in the propositus (non mutant) DcE/dce results from non reciprocal in utero transfusion received from the mutant (dcE/dce) twin. 2. The cleavage occurs after two post-zygotic mitosis : an assymetrical cleavage of these cells during the twin formation process would initiate one twin from one of dce/dcE cells and another twin arising from one dce/dcE and two dce/DcE cells. In this hypothesis no mechanism of inter-twin transfusion is necessary to account for the Rh chimerism.

22 independent man-hamster (HGPRT−) hybrids using male human cells with balanced reciprocal translocation t(X;2)(p22;q32) were analysed for human genes localized on chromosome 2 (IDHS, MDHS), on chromosome X (PGK, αGAL, G6PD) and for the different chromosomes in relation with the balanced reciprocal translocation (chr.2, chr.2q−, chr.Xp+).

On compare un groupe de 50 patients, âges de plus de 65 ans et admis successivement dans les hopitaux desservant Camberwell (Londres), avec un groupe analogue de 50 patients admis dans les hopitaux...

SUMMARYA child, aged 11, with female phenotype, associating a sacrococcygeal agenesis to Bonnevie-Ullrich's syndrome, without gonadal dysgenesis, is described. The patient's caryotype is a normal female one (44 A, XX). No similar cases could be found in the literature.This association of two syndromes of undetermined origin is probably fortuitous. A genetic study of 65 pedigrees from the literature did not reveal a mendelian type of inheritance. The possibility of external factors having occurred during embryonic life is discussed.

SUMMARYThe authors report on six patients exhibiting a congenital heart disease and malformations of the upper limbs. In two of them this association is similar to that described by Holt and Oram in 1960: atrial septal defect, heart arrythmia and abnormal thumbs. The other four patients have the same skeletal anomalies but different heart malformations. Dermatoglyphic studies revealed a high frequency of a distal position of the axial triradius and of an equivalent of a simian crease. The karyotypes are all normal. The etiology is discussed.

SUMMARYThe Authors report on a pair of MZ twins, only one of which affected by the Duchenne-type myopathy. Monozygosity is supported by the success of a reciprocal skin-graft.Various hypotheses are discussed, including that of a somatic mutation during the first division of the egge producing the twins.

Resume Sur un total de 24 cas d'evolution clonale observes au cours d'une leucemie myeloide chronique (LMC), 11 obeissaient a un meme modele, defini par la presence du chromosome Ph1, la perte d'un chromosome 17–18, et l'acquisition d'un marqueur mediocentrique de la taille d'un C. La majorite des cellules observees (85%) sont statistiquement compatibles avec l'hypothese que le chromosome marqueur est un isochromosome pour le bras long d'un 17. Il existe cependant 15% de cellules qui ont perdu un 17, sans avoir acquis le marqueur, ou inversement. Elles peuvent correspondre, respectivement, a des cellules complementaires du clone majoritaire, ou a des duplications du 17 restant. La possibilite d'autres remaniements est egalement discutee pour expliquer la perte du 17 et la formation du marqueur. Ce modele parait tres frequent. Il pourrait representer la moitie des evolutions clonales au cours des LMC. Les particularites cliniques sont discutees.

SUMMARYThe authors have studied the frequency and nature of associated malformations in a series of 1000 patients with congenital heart disease. Etiological factors have been statistically analyzed, too.

Resume Le nombre total de dermatoglyphes a eteetudie dans un echantillon de 584 paires de jumeaux MZ et DZ. 1 Le nombre moyen de cretes est plus grand chez les garcons que chez les filles. Le nombre de cretes est superieur a la main droite. 2 La distribution du nombre de cretes a ete comparee a une distribution gaussienne ajustee. L'asymetrie (skewness) et la kurtosis des distributions ont ete mesurees. 3 Les coefficients de correlation ont ete calcules dans les differents groupes de couples gemellaires pour les mains separees et pour les deux mains reunies. 4 La distribution des differences du nombre de cretes a eteetudiee. L'utilisation de cette valeur a ete decrite pour le diagnostic de la zygotie des couples de jumeaux. 5 L'ensemble des resultats a ete discute du point de vue de la determination genetique des dermatoglyphes.

The pattern of DNA synthesis in the chromosomes of Group 4–5 has been analysed in cells from individuals with the cri du chat syndrome. The abnormal chromosome, a No. 5, is one of the pair characterized by relatively early completion of synthesis in the long arms. The two remaining members of this group, characterized by extensive late replication throughout their lengths, therefore may now be recognized as the Nos. 4.

A 20-yr-old chromatin-positive true hermaphrodite, raised as a boy, presenting with breast development and menstruation, is described, who had a left ovary and a right ovotestis. Ovarian tissue appeared histologically normal, with complete maturation of graafian follicles and corpus luteum formation. In the testicular part of the ovotestis, spermatogenesis was incomplete; Leydig cells appeared normal. XX/XY mosaicism was found. Gonadal stimulation by chorionic gonadotropin, under adrenal suppression, showed normal function of the left ovary, considering that the test was performed during the hypothermic phase of the cycle. In contrast, the Leydig tissue of the ovotestis was hormonally inactive, and ovarian secretion was notably insufficient. This is perhaps due to prolonged treatment by testosterone. Serologic studies showed a double haptoglobin phenotype, suggesting that the XX/XY mosaicism was due to double fertilization of the ovum.

In this study the authors attempted to determine the frequency of the classical chromosomal syndromes as a cause of congenital heart disease and sought other cytogenetic abnormalities in patients with congenital heart disease, selected either for the presence of extracardiac abnormalities or the existence of congenital heart disease in other members of the family. Of the 275 patients whose karyotypes were determined, 119 had a known syndrome. A chromosomal aberration, such as trisomy 21, a sex chromosomal aneuploidy, such as XO, XXY, XYY, XXX, or a more complex mosaic was found in 39. Among the other patients of this group, only a patient with Fanconi's anemia showed abnormalities of the karyotype (numerous chromatid and isochromatid breaks). Among 100 other patients with unclassifiable associated malformations, 10 had abnormal karyotypes. The following abnormalities were noted: complex structural rearrangements, minute chromosome fragments, variations in size of the satellites, presence of unusual satellites on chromosome 17, deletion of the short arm of a D-chromosome, lengthening of chromosome 16, and chromosome breaks. The remaining 56 patients were studied for familial congenital heart disease. Two chromosomal abnormalities were detected in this group. If the classical aberrations are included, the frequency of chromosomal abnormalities as a cause of congenital heart disease may be estimated at between 3 and 5%. This figure should be considered in relation to the methods of recruitment which excluded all patients less than 3 years of age.

With the recently cloned complementary DNA probe, lambda Am4 for the chromosome 21 gene encoding brain amyloid polypeptide (beta amyloid protein) of Alzheimer's disease, leukocyte DNA from three patients with sporadic Alzheimer's disease and two patients with karyotypically normal Down syndrome was found to contain three copies of this gene. Because a small region of chromosome 21 containing the ets-2 gene is duplicated in patients with Alzheimer's disease, as well as in karyotypically normal Down syndrome, duplication of a subsection of the critical segment of chromosome 21 that is duplicated in Down syndrome may be the genetic defect in Alzheimer's disease.

Hypomelanosis of Ito (incontinentia pigmenti achromians), a sacrococcygeal complex dysembryoma, seizures, severe cerebral lesions, mental retardation, chorioretinal atrophy, hemihypotrophy of the body, and skeletal anomalies are reported in a female infant of North African origin. Karyotype analysis revealed mosaicism for a microdeletion of the proximal region of 15q similar to that observed in Willi-Prader syndrome. The possibility of gene assignment of Ito's disease or that it may represent a nonspecific marker for mosaicism are discussed.

L'hermaphrodisme vrai est une forme relativement rare d'état intersexué.L'étude chromosomique, dans les cas de ce genre, montre habituellement soit des caryotypes normaux XX ou XY, soit des mosaïques chromosomiques, par exemple XX/XO. Ces mosaïques sont explicables d'une façon simple par les mécanismes généralement invoqués: non-disjonction gamétique, ou bien perte et non-disjonction chromatidienne, lors des premières mitoses du zygote.Nous avons eu l'occasion d'observer un sujet de 20 ans atteint d'un hermaphrodisme vrai. Elevé comme un garçon, son aspect était ambigu: les poils du visage étaient rares, la pilosité pubienne de type féminin, la forme du bassin féminine, elle aussi; il existait une gynécomastie, la verge était de très petite dimension et les bourses étaient vides.Une laparotomie exploratrice a montré la présence de tissu testiculaire et ovarien dans les gonades, ce qu'ont démontré les examens histologiques (Prof. Nezelof). A gauche, la gonade était constituée exclusivement de tissu ovarien. A droite, il s'agissait d'une glande mixte, d'un ovotestis. Les coupes histologiques ont décelé, en effet, à côté de tissu ovarien et de formations annexielles, des tubes séminifères et une formation épididymaire.L'examen des frottis buccaux a montré l'existence de masses chromatiniennes dans 20% des noyaux cellulaires.

An orang-utan family is reported in which the father (Piku) is homozygous for a pericentric inversion of chromosome 3 and heterozygous for a structural rearrangement of chromosome 12 (author's nomenclature for this species). The latter is interpreted as transposition of the centromere by insertion into band q213 [ins cen(12)(q213)]. Piku's mate has a normal female chromosome complement. His daughters by this mate (Agnès and Ursula) are heterozygous for both his rearrangements. A fifth orang-utan (Arnold) captured on a different Malesian island was found to have one chromosome 12 similar to that of Piku, and to have a female complement, even though his keapers considered him male. Several hypotheses are proposed to explain the observations, including consanguinity, the existence of a common polymorphism in the species, and the existence of an established subspecies among orang-utans.

'True' microcephaly is associated with extremely varied ocular abnormalities, the most frequent being squint and optic atrophy. Within the heterogeneous group of the microcephalies it seems we can isolate a syndrome consisting of microcephaly, mental retardation, chorioretinal dysplasia and sometimes microphthalmia and embryological remnants such as persistence of the primary vitreous or persistence of its minor forms. Genetic transmission of such anomalies is generally considered to be autosomal recessive. The cases we are reporting on suggest that in some cases dominant transmission can be incriminated.

A patient is reported with del11p13, low catalase level, nephroblastoma, chordee and cryptorchidism, no evident mental retardation, and with normal irides. This unique observation suggests the following order of loci in 11p13, from centromere to telomere: catalase, Wilms tumor, aniridia. The chromosomal origin of nephroblastoma may be more frequent than estimated on the basis of its association with aniridia.