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We present a boy with a rare unbalanced translocation 46,XY,-15,+der(22),t(15;22)(q13;q11) pat. Previous reports of similar chromosome findings mention only the Prader-Willi phenotype. At birth, his manifestations included severe hypotonia and lethargy, (typical of deletion of 15pter----q13); hypertelorism, down-slanting small palpebral fissures, preauricular tags, long philtrum (typical of duplication of 22pter----q11); severe laryngotracheomalacia, and proximal implantation of the thumb. In a review of the literature on chromosome abnormalities involving duplication of 22q11 the associated clinical phenotype consists of mild mental retardation, microcephaly, hypotonia, hypertelorism, down-slanting palpebral fissures, a long philtrum, cleft or highly arched palate, and ear abnormalities. Preauricular pits or tags are common. Cardiovascular defects, renal and genital problems and dislocated hips are frequently present. Anal atresia and colobomata are mainly seen in cat-eye syndrome, the phenotype associated with idic 22q11. Our findings indicate that patients with unbalanced t(15;22) can have manifestations of the dup 22q11, in addition to the previously reported Prader-Willi phenotype, even if the duplicated segment is small.

Molybdenum cofactor deficiency is characterized by the absence of sulphite oxidase, xanthine dehydrogenase and aldehyde oxidase, the three known enzymes in man that require the cofactor for their activity. Prenatal diagnosis of the deficiency may be performed by assay of sulphite oxidase activity in cultured amniocytes. However, the activity in amniocytes is low and large numbers of cells are required for reliable assessment. We show that sulphite oxidase is present at high levels in chorionic villi obtained at 10-14 weeks gestation and can be assayed directly in the biopsy sample without cell culture. This assay has been applied to two pregnancies at risk for molybdenum cofactor deficiency with successful diagnoses of an unaffected and an affected fetus.

An acardiac anomaly (holoacardius anceps) showed advanced development of the head and lower body parts in the absence of all thoracic and upper abdominal viscera. Large vascular anastomoses in the vertebral canal formed the only blood supply to the head. The two-vessel umbilical cord of the acardius contained calcified mural thrombi in both vessels. Severe fetal hydrops resulted in an exceptionally large birth weight of 3720 g. Fibroblasts from the acardius showed chromosomal mosaicism. The surviving co-twin was remarkable for a widely patent ductus arteriosus, unilateral multicystic renal dysplasia, and a normal chromosome complement. The circumscribed absence of organ development in the thorax and upper abdomen of the acardius and the vascular anatomy with thrombosis of the umbilical vessels suggest that an occlusion of thoracic and abdominal vessels was significant in the development of this acardiac malformation and should be considered as a possible pathogenetic mechanism in similar cases of acardia.

We studied two families with an inherited deletion of the short arm of an X chromosome (Xp) in which affected male offspring have epiphyseal stippling in infancy (chondrodysplasia punctata), nasal hypoplasia, ichthyosis, and mental retardation. The presence of ichthyosis and the apparent pattern of X-linked recessive inheritance prompted investigation of the short arm of the X chromosome through studies of genetic markers and focused cytogenetic analysis. Biochemical studies suggested that there was a deletion of three genes previously mapped to the X-chromosome short arm, including the steroid sulfatase locus, the Xg locus, and the M1C2X locus. Prometaphase chromosomes demonstrated a deletion of Xp at p22.32 in the affected boys, in their obligate-carrier mothers, and in 11 of 25 women at risk as potential carriers. The women carrying the Xp deletion had normal gonadal function and fertility but were shorter than the noncarriers in their families (P less than 0.00001). These findings have implications for the genetic organization of this portion of the human X chromosome and demonstrate that small cytogenetic abnormalities may account for disorders with apparent mendelian patterns of inheritance.

When fetuses and placentas were removed on Day 18 in normal pregnant rabbits, plasma progesterone levels declined rapidly to non-pregnant values within 48 h. This decline was largely prevented if only fetectomy was performed, leaving the placentas in situ, but not when the fetal components of the placentas were also removed. These results suggested that ovarian progesterone production was dependent upon trophic influences emanating from the fetal portions of the placentas. Ovarian progesterone production was maintained by an extract of rabbit pituitaries for at least 72 h after removal of fetuses and placentas.

Fetectomy, either alone or combined with ovariectomy, was performed in 17 monkeys. Following fetectomy alone in 8 animals, progesterone values were maintained at normal pregnancy levels (1.0 ng/cc plasma or more), until expulsion of the placenta, which frequently occurred at a time well past normal term. Values declining toward but not reaching the nonpregnancy range were observed in some animals in the 2 to 6 weeks preceding expulsion; no similar decline occurs preceding normal labor. In all cases, after the placenta was expelled, progesterone values fell below 1 ng/cc plasma within 2 days. When ovariectomy was superimposed on 3 animals previously fetectomized, plasma progesterone values fell abruptly to nonpregnancy levels, and the placenta was expelled in an average of 6.3 days. The source of the progesterone in these fetectomized animals was, therefore, the ovaries, not the placenta damaged by a preceding fetectomy. However, the ovarian progesterone production after fetectomy was dependent on the continued presence of the placenta. In 6 animals following ovariectomy, and with an intact fetus and placenta, plasma progesterone levels were usually maintained at normal pregnancy levels. When fetectomy was superimposed in these animals with a preceding ovariectomy, plasma progesterone levels fell into the nonpregnancy range in an average of 4.8 days, and placental expulsion occurred after an average of 30.8 days. We believe this reflected a deteriorating ability of the fetectomized placenta to produce progesterone, which was capable only transiently of maintaining plasma values, but later of exerting sufficient local effect to maintain uterine quiescence for a longer time.

Our studies were designed to determine whether changing peripheral progesterone levels in rabbits reflected changing metabolic clearance rates (MCR) or changing production rates (PR), or both. Plasma progesterone concentrations rise from nonpregnancy levels to peak values at the end of the first third of gestation and at midpseudopregnancy. In the pregnant rabbit, these decline slowly during the second third of gestation and then more rapidly until near nonpregnancy values are reached at term. Progesterone levels decline sharply during the second half of pseudopregnancy. During pregnancy and pseudopregnancy, we found only small variations in MCRs which cannot account for the approximately 10-fold increase in plasma progesterone concentrations. The increases can, however, be accounted for by changes in PRs which rose sharply after conception of hCG injection to 14-fold the nonpregnancy level on day 16 of gestation and 11-fold on day 7 of pseudopregnancy. These results indicate that changes in ovarian PRs are the major factor for the variations in peripheral progesterone levels during pregnancy and pseudopregnancy. The rabbit differs in this respect from the guinea pig, in which changing progesterone concentrations during pregnancy were shown to reflect sharply reduced MCRs. After a single injection of progesterone in 20-day pregnant rabbits, the disappearance of the steroid from the circulation consisted of two components; an initial phase during which progesterone disappeared rapidly (t1/2 = 2.4 +/- 0.2 min) followed by a slower rate of disappearance (t1/2 = 21.5 +/- 2.2 min).

A newborn infant with a 47,XY,+ der(.),t(1;9) (p36;q22)mat chromosome complement and the clinical features of the 9p trisomy is described. A review of the reproductive histories of five cases with trisomy 9pter yields 9q21 or 22 indicate that the balanced translocation mothers of these infants may have as high as a 23% chance of producing a chromosomally unbalanced offspring due to 3:1 disjunction.

Peripheral plasma progesterone (P) levels in the rhesus monkey remain relatively constant both during the latter half of pregnancy and for long periods after fetectomy (removal of the fetus with the placenta left in situ) or ovariectomy. The constancy is maintained despite what appears to be reciprocal changes in the relative contributions of ovary and placenta. Placental regulation of the corpus luteum is likely, but it is not known if the corpus luteum responds to a gonadotropic stimulus in the later stages of pregnancy. In this study, we have investigated the effects of hCG administration in postdelivery monkeys (normally pregnant, fetectomized, ovariectomized and sham ovariectomized animals) and have determined if hCG administration maintains plasma P at pregnancy levels. hCG maintained P at pregnancy levels after surgical removal of the conceptus near term in both normally pregnant and previously fetectomized monkeys over a 7-day treatment period. hCG treatment after normal delivery maintained P levels in sham-ovariectomized but not in ovariectomized monkeys over an 8-day treatment period. The magnitude of the response to hCG declines over the treatment period in all groups except fetectomized monkeys, although hCG levels in the peripheral plasma are quite constant. These results indicate that the ovary of late pregnancy is fully capable of producing P at normal values and is responsive to this gonadotropin.

The metabolic clearance rate (MCR) and production rate (PR) of progesterone were measured in rhesus monkeys both before and during intravenous infusion of progesterone at rates which approximately doubled or tripled the peripheral plasma levels. The monkeys were normally pregnant or fetectomized and were studied during the second half of pregnancy. Raising the peripheral plasma levels did not significantly after the MCR or the PR of progesterone. We conclude that peripheral progesterone levels are not the factor which controls the PR of progesterone in rhesus monkeys.

Restriction-fragment-length-polymorphism analysis was used to examine a female who is segregating for Duchenne muscular dystrophy (DMD) and a deletion of the DXS164 region of the X chromosome. The segregating female has no prior family history of DMD, and she has two copies of the DXS164 region in her peripheral blood lymphocytes. The following two hypotheses are proposed to explain the coincidence of the DMD phenotype and deletion of the DXS164 region in her offspring: (1) she may be a gonadal mosaic for cells with two normal X chromosomes and cells with one normal X chromosome and an X chromosome with a deletion of the DXS164 region; and (2) she may carry a familial X;autosome translocation in which the DXS164 region is deleted from one X chromosome and translocated to an autosome. The segregation of DMD and the DXS164 deletion in this family illustrates the importance of extended pedigree analysis when DXS164 deletions are used to identify female carriers of the DMD gene.

The mammalian fetus affixed to the uterine wall in some ways resembles a homograft, but maternal homograft immunity even when specifically directed against her fetuses fails to destroy them. The placental barrier appears to be critical in protecting the fetus against maternal immunologic attack. In order to evaluate the means by which it affords protection, we have measured in rabbits the transfer of cytotoxic antibody from mother to fetus. When the offspring were not the specific targets for maternal antibody, we found titers of cytotoxic antibody in the newborn animals at or near maternal levels in 16 of 18 cases (89 per cent), demonstrating the ability of this antibody to cross the rabbit placenta. When the offspring were appropriate targets for antibody, however, 11 of 18 newborn animals (61 per cent) had no demonstrable titer. We believe that in these latter cases, antibody had become fixed to antigenic sites and thereby had been removed from the fetal circulation. There was, however, no evidence of harm to any of the fetuses, either in survival (as demonstrated in a previous study) or in spleen or thymus weights or peripheral leukocyte and mononuclear cell counts. Cytotoxic antibody appears to reach the embryo early in gestation, since we found antibody in 8-day-old blastocyst fluid in each of 2 trials. We conclude that the fetus neither receives nor requires protection against cytotoxic antibody, and believe that fetal protection against maternal homograft immunity is afforded by a placental barrier to maternal mononuclear leukocytes.