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Monosomy of terminal 16p13.3 is a relatively common subtelomeric abnormality, most affected individuals presented α-thalassemia, some also have mental retardation, developmental abnormalities and/or speech delay and facial dysmorphism, which is termed ATR-16 syndrome. Here, we reported two novel 16p13.3 deletions involving the α-globin gene cluster and multispecies conserved sequences (MCSs), causing only a phenotype of α-thalassemia.Samples were collected from members of the two families and were subjected to haematological and comprehensive genetic analysis.The novel 108 Kb deletion in family A extends from the non-protein coding RNA gene (WASIR2) to the NPRL3 gene, removing MCS-R1 to R3. This deletion should arise de novo because it wasn't detected in both parents. The novel 336 Kb deletion in family B should extend from telomere to ∼ chr16:336000, removing the entire α-globin gene cluster. Carriers of these two deletions presented with microcytosis and hypochromic red cells, in accordance with a phenotype of αOur study increases the mutation spectrum of α-thalassemia. MCSs deletion should be considered in clinical practice of thalassemia screening and diagnosis.

Additional file 1. Table S1. Estimated pathogenic variants in KLHL40 in our local database on ACMG guidelines. Table S2. Estimated pathogenic or likely pathogenic variants in KLHL40 in Chigene database on ACMG guidelines.

We describe the prenatal diagnosis and fetal phenotype of partial trisomy 12 (p12-pter) transmitted from a maternal reciprocal translocation 6;12. Genetic analysis of umbilical cord blood of a 27-year-old woman, gravida 4, para 1 at 35 weeks' gestation due to a tricuspid regurgitation and orbital hypertelorism by sonography revealed an unusual karyotype of 46, XY, der (6) t (6;12) (p24;p12) mat. The pregnancy was terminated at 37 gestational weeks. The proband postnatally displayed by dysmorphic features of a round flat face with prominent cheeks and high forehead, hypertelorism, a short nose, a broad and depressed nasal bridge, anteverted nares, a deformed philtrum, an open mouth, thin upper vermilion and broad everted lower lip, low-set ears and aural atresia, broad hands with simian creases, and a short neck. By anatomy, the fetal was found to have right artery catheter vagus, congenital cataract, no turbinate and external auditory canal. Through the karoytpye-phynotpye analysis on the present patient and a review of other reported cases, we believed that the case was the first report, which expanded the database of partial trisomy 12p, and was of benefit for future clinical genetic counseling. At the same time, this study supported the viewpoint that phenotypic variability depends on the type and extent of the associated partial monosomy.