P–559 Proof of principle for Extended Carrier Screening (ECS) in medically assisted reproduction: First 33 cases of genetic matching for donors and recipients

Study question

Does implementation of ECS to reduce reproductive risk when using a donor with a known carrier status serves as a wider model for ART patients.

Summary answer

ECS should be routinely offered to ART patients using their own or donor gametes to reduce risk of having a child with a recessive condition.

What is known already

Responsible implementation of ECS in assisted reproduction is required as commercial offerings increase and become more accessible; ESHRE ethical guidelines are shortly to be published after consideration of stakeholder reviews. Increasingly ECS is included in donor screening, rejecting potential donors for a known carrier status will reduce donor gamete availability. Clinics should consider potential match yield in carrier panels to develop tools and specialist support to deliver and guide patients to help make informed decisions for ECS.

Study design, size, duration

Retrospective evaluation of ECS results for the first 33 patients who undertook counter screening in the clinic setting from April 2020 to December 2020 before using a donor with known carrier status. The findings would serve as proof of concept for wider application.

Participants/materials, setting, methods

Patients had opted to undertake ECS after discussion of risk estimates, family history review and personal options.Testing was commissioned between two ECS providers for international donor banks using panels of 283+ genes. Incidence of carrier match, the number of variants reported, and their clinical significance were reviewed. Main results and the role of chance: Of the 33 co-carrier tests, one carrier match for a patient and potential donor was identified. 41%, 26%, 9% and 3% of patients were carriers of 1, 2, 3 and 4 pathogenic variants respectively in 30 different genes. In 21% of patients, no pathogenic variants were reported. Of the variants identified as incidental findings, six were actionable and eligible for cascade screening to the wider family. This included Cystic Fibrosis, Sickle cell and Thalassemia. A variant for Familial hypercholesterolemia had preventative value. An incidental finding of a fragile X pre-mutation allowed for PGT-M as part of planned treatment

Limitations, reasons for caution

Findings from this first cohort of 33 tests may not represent the general population, follow up evaluation as participant numbers increase is required.

Wider implications of the findings: Implementation of guidelines is required to ensure consistency of methodology and availability of transparent information for ECS to ART patients. Incidental findings may be of value to the patient and wider family.

Trial registration number

Not applicable

Examining the temporality of vitamin E acetate in illicit THC-containing e-cigarette, or vaping, products from a public health and law enforcement response to EVALI - Utah, 2018-2020

BACKGROUND

In the summer of 2019, e-cigarette, or vaping, product use-associated lung injury (EVALI) was detected in the United States. Multiple agencies reported illicit tetrahydrocannabinol (THC)-containing e-cigarette, or vaping, products containing vitamin E acetate (VEA) as a substance of concern.

METHODS

As an expansion of the Utah Department of Health's response to EVALI, the Utah Public Health Laboratory and the Utah Department of Public Safety screened 170 products from 96 seizures between October 2018 and January 2020. Using Pearson's correlation coefficient, we analyzed the temporal correlation of national, and Utah specific case counts, and the percentage of seizures indicating VEA by month.

RESULTS

The findings indicate strong and significant correlations between seizures indicating VEA and both the national (r = 0.70, p = 0.002) and Utah specific (r = 0.78, p < 0.001) case counts.

CONCLUSION

These findings underscore that VEA should not be added to e-cigarettes, or vaping, products and the importance of collaboration with law enforcement when responding to outbreaks associated with illicit substances.

Phthalate-associated hypertension in premature infants: a prospective mechanistic cohort study

BACKGROUND

Phthalates are associated with increased blood pressure in children. Large exposures to di-(2-ethylhexyl) phthalate (DEHP) among premature infants have been a cause for concern.

METHODS

We conducted a prospective observational cohort study to determine if DEHP exposures are related to systolic blood pressure (SBP) in premature infants, and if this exposure is associated with activation of the mineralocorticoid receptor (MR). Infants were monitored longitudinally for 8 months from birth. Those who developed idiopathic hypertension were compared with normotensive infants for DEHP exposures. Appearance of urinary metabolites after exposure was documented. Linear regression evaluated the relationship between DEHP exposures and SBP index and whether urinary cortisol/cortisone ratio (a surrogate marker for 11β-HSD2 activity) mediated those relationships. Urinary exosomes were quantified for sodium transporter/channel expression and interrogated against SBP index.

RESULTS

Eighteen patients met the study criteria, nine developed transient idiopathic hypertension at a postmenstrual age of 40.6 ± 3.4 weeks. The presence of urinary DEHP metabolites was associated with prior IV and respiratory tubing DEHP exposures (p < 0.05). Both IV and respiratory DEHP exposures were greater in hypertensive infants (p < 0.05). SBP index was related to DEHP exposure from IV fluid (p = 0.018), but not respiratory DEHP. Urinary cortisol/cortisone ratio was related to IV DEHP and SBP index (p < 0.05). Sodium transporter/channel expression was also related to SBP index (p < 0.05).

CONCLUSIONS

Increased blood pressure and hypertension in premature infants are associated with postnatal DEHP exposure. The mechanism of action appears to be activation of the MR through inhibition of 11β-HSD2.

Classical anomia: a neuropsychological perspective on speech production

We present data collected from two anomic aphasics. Thorough assessment of comprehension, oral reading and repetition revealed no underlying impairments suggesting that both patients were examples of classical anomia--word-finding difficulties without impaired semantics or phonology. We describe a series of experiments in which the degree of anomia was both increased and decreased, by cueing or priming with either a semantically related word or the target item. One of the patients also presented with an 'acquired' tip-of-the-tongue phenomenon. He was able to indicate with a high-degree of accuracy the syllable length of the target, and whether or not it was a compound word. Neither patient could provide the first sound/letter. The data are discussed in terms of discrete two-stage models of speech production, an interactive-activation theory and a distributed model in which the positive and negative computational consequences of the arbitrary relationship between sound and meaning are emphasised.

A ceramic system for delivering interleukin-2

Interleukin-2 (IL-2) is a potentially effective cytokine to be used for cancer treatment. Since keeping IL-2 doses at a low, continuous level is important to avoid side effects which accompany high IL-2 doses, a ceramic which release IL-2 could prove to be a beneficial method of drug delivery for cancer patients [1]. In vitro studies were performed to determine the optimal hydroxyapatite (HA) to IL-2 ratio for continuous release of IL-2 from HA using both a matrix and insert ceramic pellet. In the matrix pellet experiment, HA to IL-2 ratios of 25:1, 50:1 and 100:1 were tested by compressing a homogenous mixture of each variable in triplicate and placing each ceramic in 2.5 mL simulated body fluid (SBF) at 37 degrees C. The fluid was collected and replaced for each ceramic every two hours for 12 hours and at 24 hours. The collected fluid was then assayed for IL-2 content. Pellets consisting of 25:1 ceramic to drug ratio delivered almost the entire amount of IL-2 at the fastest rate. Composites of 100:1 IL-2 to HA delivered the least amount of IL-2 at the slowest rate. Release of IL-2 from the 50:1 ratio pellets was intermediate with respect to speed and amount of delivery. In the insert pellet experiment, similar laboratory procedures were used to show that 100:1 ratio insert pellets delivered IL-2 at a slower rate and in lesser amounts than 50:1 ratio insert pellets. Results of this study show that HA can deliver IL-2 at different rates by varying the ratio of HA to IL-2 in both matrix and insert ceramic pellets.