Large Scale Next Generation Sequencing and Newborn Screening: Are We Ready?

A multicenter prospective study of next-generation sequencing-based newborn screening for monogenic genetic diseases in China

BACKGROUND

Newborn screening (NBS) is an important and successful public health program that helps improve the long-term clinical outcomes of newborns by providing early diagnosis and treatment of certain inborn diseases. The development of next-generation sequencing (NGS) technology provides new opportunities to expand current newborn screening methodologies.

METHODS

We designed a a newborn genetic screening (NBGS) panel targeting 135 genes associated with 75 inborn disorders by multiplex PCR combined with NGS. With this panel, a large-scale, multicenter, prospective multidisease analysis was conducted on dried blood spot (DBS) profiles from 21,442 neonates nationwide.

RESULTS

We presented the positive detection rate and carrier frequency of diseases and related variants in different regions; and 168 (0.78%) positive cases were detected. Glucose-6-Phosphate Dehydrogenase deficiency (G6PDD) and phenylketonuria (PKU) had higher prevalence rates, which were significantly different in different regions. The positive detection of G6PD variants was quite common in south China, whereas PAH variants were most commonly identified in north China. In addition, NBGS identified 3 cases with DUOX2 variants and one with SLC25A13 variants, which were normal in conventional NBS, but were confirmed later as abnormal in repeated biochemical testing after recall. Eighty percent of high-frequency gene carriers and 60% of high-frequency variant carriers had obvious regional differences. On the premise that there was no significant difference in birth weight and gestational age, the biochemical indicators of SLC22A5 c.1400C > G and ACADSB c.1165A > G carriers were significantly different from those of non-carriers.

CONCLUSIONS

We demonstrated that NBGS is an effective strategy to identify neonates affected with treatable diseases as a supplement to current NBS methods. Our data also showed that the prevalence of diseases has significant regional characteristics, which provides a theoretical basis for screening diseases in different regions.

Psychological and Ethical Challenges of Introducing Whole Genome Sequencing into Routine Newborn Screening: Lessons Learned from Existing Newborn Screening

As a psychologist and an ethicist, we have explored empirically newborn screening consent and communication processes. In this paper we consider the impact on families if newborn screening uses whole genome sequencing. We frame this within the World Health Organization's definition of health and contend that proposals to use whole genome sequencing in newborn screening take into account the ethical, practical and psychological impact of such screening. We argue that the important psychological processes occurring in the neonatal phase necessitate a clear justification that providing risk information at this stage provides a health benefit. We illustrate how research on current newborn screening can inform whole genome sequencing debates, whilst highlighting important gaps. Obtaining explicit, voluntary, and sufficiently informed consent for newborn screening is challenging, however we stress that such consent is ethically and legally appropriate and psychologically and practically important. We conclude by outling how this might be done.